diff --git a/NEWS b/NEWS
index 0037c3bb..08c01f20 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,10 @@
+What's new in psycopg 2.4.2
+---------------------------
+
+  - Fixed escape for negative numbers prefixed by minus operator
+    (ticket #57).
+
+
 What's new in psycopg 2.4.1
 ---------------------------
 
diff --git a/lib/extensions.py b/lib/extensions.py
index 82e17fa4..838d8691 100644
--- a/lib/extensions.py
+++ b/lib/extensions.py
@@ -39,7 +39,7 @@ from psycopg2._psycopg import DECIMALARRAY, FLOATARRAY, INTEGERARRAY, INTERVALAR
 from psycopg2._psycopg import LONGINTEGERARRAY, ROWIDARRAY, STRINGARRAY, TIMEARRAY
 from psycopg2._psycopg import UNICODEARRAY
 
-from psycopg2._psycopg import Binary, Boolean, Float, QuotedString, AsIs
+from psycopg2._psycopg import Binary, Boolean, Int, Float, QuotedString, AsIs
 try:
     from psycopg2._psycopg import MXDATE, MXDATETIME, MXINTERVAL, MXTIME
     from psycopg2._psycopg import MXDATEARRAY, MXDATETIMEARRAY, MXINTERVALARRAY, MXTIMEARRAY
diff --git a/psycopg/adapter_pdecimal.c b/psycopg/adapter_pdecimal.c
index 9b573467..e14e7694 100644
--- a/psycopg/adapter_pdecimal.c
+++ b/psycopg/adapter_pdecimal.c
@@ -41,8 +41,10 @@ pdecimal_getquoted(pdecimalObject *self, PyObject *args)
     PyObject *check, *res = NULL;
     check = PyObject_CallMethod(self->wrapped, "is_finite", NULL);
     if (check == Py_True) {
-        res = PyObject_Str(self->wrapped);
-        goto end;
+        if (!(res = PyObject_Str(self->wrapped))) {
+            goto end;
+        }
+        goto output;
     }
     else if (check) {
         res = Bytes_FromString("'NaN'::numeric");
@@ -70,16 +72,39 @@ pdecimal_getquoted(pdecimalObject *self, PyObject *args)
         goto end;
     }
 
-    res = PyObject_Str(self->wrapped);
+    /* wrapped is finite */
+    if (!(res = PyObject_Str(self->wrapped))) {
+        goto end;
+    }
+
+    /* res may be unicode and may suffer for issue #57 */
+output:
+
 #if PY_MAJOR_VERSION > 2
     /* unicode to bytes in Py3 */
-    if (res) {
+    {
         PyObject *tmp = PyUnicode_AsUTF8String(res);
         Py_DECREF(res);
-        res = tmp;
+        if (!(res = tmp)) {
+            goto end;
+        }
     }
 #endif
 
+    if ('-' == Bytes_AS_STRING(res)[0]) {
+        /* Prepend a space in front of negative numbers (ticket #57) */
+        PyObject *tmp;
+        if (!(tmp = Bytes_FromString(" "))) {
+            Py_DECREF(res);
+            res = NULL;
+            goto end;
+        }
+        Bytes_ConcatAndDel(&tmp, res);
+        if (!(res = tmp)) {
+            goto end;
+        }
+    }
+
 end:
     Py_XDECREF(check);
     return res;
diff --git a/psycopg/adapter_pfloat.c b/psycopg/adapter_pfloat.c
index 715ed8f2..1b8074f9 100644
--- a/psycopg/adapter_pfloat.c
+++ b/psycopg/adapter_pfloat.c
@@ -49,18 +49,37 @@ pfloat_getquoted(pfloatObject *self, PyObject *args)
             rv = Bytes_FromString("'-Infinity'::float");
     }
     else {
-        rv = PyObject_Repr(self->wrapped);
+        if (!(rv = PyObject_Repr(self->wrapped))) {
+            goto exit;
+        }
 
 #if PY_MAJOR_VERSION > 2
         /* unicode to bytes in Py3 */
-        if (rv) {
+        {
             PyObject *tmp = PyUnicode_AsUTF8String(rv);
             Py_DECREF(rv);
-            rv = tmp;
+            if (!(rv = tmp)) {
+                goto exit;
+            }
         }
 #endif
+
+        if ('-' == Bytes_AS_STRING(rv)[0]) {
+            /* Prepend a space in front of negative numbers (ticket #57) */
+            PyObject *tmp;
+            if (!(tmp = Bytes_FromString(" "))) {
+                Py_DECREF(rv);
+                rv = NULL;
+                goto exit;
+            }
+            Bytes_ConcatAndDel(&tmp, rv);
+            if (!(rv = tmp)) {
+                goto exit;
+            }
+        }
     }
 
+exit:
     return rv;
 }
 
diff --git a/psycopg/adapter_pint.c b/psycopg/adapter_pint.c
new file mode 100644
index 00000000..ad89a06b
--- /dev/null
+++ b/psycopg/adapter_pint.c
@@ -0,0 +1,266 @@
+/* adapter_int.c - psycopg pint type wrapper implementation
+ *
+ * Copyright (C) 2011 Daniele Varrazzo <daniele.varrazzo@gmail.com>
+ *
+ * This file is part of psycopg.
+ *
+ * psycopg2 is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * In addition, as a special exception, the copyright holders give
+ * permission to link this program with the OpenSSL library (or with
+ * modified versions of OpenSSL that use the same license as OpenSSL),
+ * and distribute linked combinations including the two.
+ *
+ * You must obey the GNU Lesser General Public License in all respects for
+ * all of the code used other than OpenSSL.
+ *
+ * psycopg2 is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+ * License for more details.
+ */
+
+#define PSYCOPG_MODULE
+#include "psycopg/psycopg.h"
+
+#include "psycopg/adapter_pint.h"
+#include "psycopg/microprotocols_proto.h"
+
+
+/** the Int object **/
+
+static PyObject *
+pint_getquoted(pintObject *self, PyObject *args)
+{
+    PyObject *res;
+    if (!(res = PyObject_Str(self->wrapped))) {
+        goto exit;
+    }
+
+#if PY_MAJOR_VERSION > 2
+    /* unicode to bytes in Py3 */
+    {
+        PyObject *tmp = PyUnicode_AsUTF8String(res);
+        Py_DECREF(res);
+        if (!(res = tmp)) {
+            goto exit;
+        }
+    }
+#endif
+
+    if ('-' == Bytes_AS_STRING(res)[0]) {
+        /* Prepend a space in front of negative numbers (ticket #57) */
+        PyObject *tmp;
+        if (!(tmp = Bytes_FromString(" "))) {
+            Py_DECREF(res);
+            res = NULL;
+            goto exit;
+        }
+        Bytes_ConcatAndDel(&tmp, res);
+        if (!(res = tmp)) {
+            goto exit;
+        }
+    }
+
+exit:
+    return res;
+}
+
+static PyObject *
+pint_str(pintObject *self)
+{
+    return psycopg_ensure_text(pint_getquoted(self, NULL));
+}
+
+static PyObject *
+pint_conform(pintObject *self, PyObject *args)
+{
+    PyObject *res, *proto;
+
+    if (!PyArg_ParseTuple(args, "O", &proto)) return NULL;
+
+    if (proto == (PyObject*)&isqlquoteType)
+        res = (PyObject*)self;
+    else
+        res = Py_None;
+
+    Py_INCREF(res);
+    return res;
+}
+
+/** the int object */
+
+/* object member list */
+
+static struct PyMemberDef pintObject_members[] = {
+    {"adapted", T_OBJECT, offsetof(pintObject, wrapped), READONLY},
+    {NULL}
+};
+
+/* object method table */
+
+static PyMethodDef pintObject_methods[] = {
+    {"getquoted", (PyCFunction)pint_getquoted, METH_NOARGS,
+     "getquoted() -> wrapped object value as SQL-quoted string"},
+    {"__conform__", (PyCFunction)pint_conform, METH_VARARGS, NULL},
+    {NULL}  /* Sentinel */
+};
+
+/* initialization and finalization methods */
+
+static int
+pint_setup(pintObject *self, PyObject *obj)
+{
+    Dprintf("pint_setup: init pint object at %p, refcnt = "
+        FORMAT_CODE_PY_SSIZE_T,
+        self, Py_REFCNT(self)
+      );
+
+    Py_INCREF(obj);
+    self->wrapped = obj;
+
+    Dprintf("pint_setup: good pint object at %p, refcnt = "
+        FORMAT_CODE_PY_SSIZE_T,
+        self, Py_REFCNT(self)
+      );
+    return 0;
+}
+
+static int
+pint_traverse(PyObject *obj, visitproc visit, void *arg)
+{
+    pintObject *self = (pintObject *)obj;
+
+    Py_VISIT(self->wrapped);
+    return 0;
+}
+
+static void
+pint_dealloc(PyObject* obj)
+{
+    pintObject *self = (pintObject *)obj;
+
+    Py_CLEAR(self->wrapped);
+
+    Dprintf("pint_dealloc: deleted pint object at %p, refcnt = "
+        FORMAT_CODE_PY_SSIZE_T,
+        obj, Py_REFCNT(obj)
+      );
+
+    Py_TYPE(obj)->tp_free(obj);
+}
+
+static int
+pint_init(PyObject *obj, PyObject *args, PyObject *kwds)
+{
+    PyObject *o;
+
+    if (!PyArg_ParseTuple(args, "O", &o))
+        return -1;
+
+    return pint_setup((pintObject *)obj, o);
+}
+
+static PyObject *
+pint_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
+{
+    return type->tp_alloc(type, 0);
+}
+
+static void
+pint_del(PyObject* self)
+{
+    PyObject_GC_Del(self);
+}
+
+static PyObject *
+pint_repr(pintObject *self)
+{
+    return PyString_FromFormat("<psycopg2._psycopg.Int object at %p>",
+                                self);
+}
+
+
+/* object type */
+
+#define pintType_doc \
+"Int(str) -> new Int adapter object"
+
+PyTypeObject pintType = {
+    PyVarObject_HEAD_INIT(NULL, 0)
+    "psycopg2._psycopg.Int",
+    sizeof(pintObject),
+    0,
+    pint_dealloc, /*tp_dealloc*/
+    0,          /*tp_print*/
+
+    0,          /*tp_getattr*/
+    0,          /*tp_setattr*/
+
+    0,          /*tp_compare*/
+
+    (reprfunc)pint_repr, /*tp_repr*/
+    0,          /*tp_as_number*/
+    0,          /*tp_as_sequence*/
+    0,          /*tp_as_mapping*/
+    0,          /*tp_hash */
+
+    0,          /*tp_call*/
+    (reprfunc)pint_str, /*tp_str*/
+
+    0,          /*tp_getattro*/
+    0,          /*tp_setattro*/
+    0,          /*tp_as_buffer*/
+
+    Py_TPFLAGS_DEFAULT|Py_TPFLAGS_BASETYPE|Py_TPFLAGS_HAVE_GC, /*tp_flags*/
+    pintType_doc, /*tp_doc*/
+
+    pint_traverse, /*tp_traverse*/
+    0,          /*tp_clear*/
+
+    0,          /*tp_richcompare*/
+    0,          /*tp_weaklistoffset*/
+
+    0,          /*tp_iter*/
+    0,          /*tp_iternext*/
+
+    /* Attribute descriptor and subclassing stuff */
+
+    pintObject_methods, /*tp_methods*/
+    pintObject_members, /*tp_members*/
+    0,          /*tp_getset*/
+    0,          /*tp_base*/
+    0,          /*tp_dict*/
+
+    0,          /*tp_descr_get*/
+    0,          /*tp_descr_set*/
+    0,          /*tp_dictoffset*/
+
+    pint_init, /*tp_init*/
+    0, /*tp_alloc  will be set to PyType_GenericAlloc in module init*/
+    pint_new, /*tp_new*/
+    (freefunc)pint_del, /*tp_free  Low-level free-memory routine */
+    0,          /*tp_is_gc For PyObject_IS_GC */
+    0,          /*tp_bases*/
+    0,          /*tp_mro method resolution order */
+    0,          /*tp_cache*/
+    0,          /*tp_subclasses*/
+    0           /*tp_weaklist*/
+};
+
+
+/** module-level functions **/
+
+PyObject *
+psyco_Int(PyObject *module, PyObject *args)
+{
+    PyObject *obj;
+
+    if (!PyArg_ParseTuple(args, "O", &obj))
+        return NULL;
+
+    return PyObject_CallFunctionObjArgs((PyObject *)&pintType, obj, NULL);
+}
diff --git a/psycopg/adapter_pint.h b/psycopg/adapter_pint.h
new file mode 100644
index 00000000..fd553e8b
--- /dev/null
+++ b/psycopg/adapter_pint.h
@@ -0,0 +1,53 @@
+/* adapter_pint.h - definition for the psycopg int type wrapper
+ *
+ * Copyright (C) 2011 Daniele Varrazzo <daniele.varrazzo@gmail.com>
+ *
+ * This file is part of psycopg.
+ *
+ * psycopg2 is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * In addition, as a special exception, the copyright holders give
+ * permission to link this program with the OpenSSL library (or with
+ * modified versions of OpenSSL that use the same license as OpenSSL),
+ * and distribute linked combinations including the two.
+ *
+ * You must obey the GNU Lesser General Public License in all respects for
+ * all of the code used other than OpenSSL.
+ *
+ * psycopg2 is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
+ * License for more details.
+ */
+
+#ifndef PSYCOPG_PINT_H
+#define PSYCOPG_PINT_H 1
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+extern HIDDEN PyTypeObject pintType;
+
+typedef struct {
+    PyObject_HEAD
+
+    /* this is the real object we wrap */
+    PyObject *wrapped;
+
+} pintObject;
+
+/* functions exported to psycopgmodule.c */
+
+HIDDEN PyObject *psyco_Int(PyObject *module, PyObject *args);
+#define psyco_Int_doc \
+    "Int(obj) -> new int value"
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* !defined(PSYCOPG_PINT_H) */
diff --git a/psycopg/psycopgmodule.c b/psycopg/psycopgmodule.c
index 01069414..99d7c6c0 100644
--- a/psycopg/psycopgmodule.c
+++ b/psycopg/psycopgmodule.c
@@ -39,6 +39,7 @@
 #include "psycopg/adapter_qstring.h"
 #include "psycopg/adapter_binary.h"
 #include "psycopg/adapter_pboolean.h"
+#include "psycopg/adapter_pint.h"
 #include "psycopg/adapter_pfloat.h"
 #include "psycopg/adapter_pdecimal.h"
 #include "psycopg/adapter_asis.h"
@@ -316,9 +317,9 @@ psyco_adapters_init(PyObject *mod)
 
     microprotocols_add(&PyFloat_Type, NULL, (PyObject*)&pfloatType);
 #if PY_MAJOR_VERSION < 3
-    microprotocols_add(&PyInt_Type, NULL, (PyObject*)&asisType);
+    microprotocols_add(&PyInt_Type, NULL, (PyObject*)&pintType);
 #endif
-    microprotocols_add(&PyLong_Type, NULL, (PyObject*)&asisType);
+    microprotocols_add(&PyLong_Type, NULL, (PyObject*)&pintType);
     microprotocols_add(&PyBool_Type, NULL, (PyObject*)&pbooleanType);
 
     /* strings */
@@ -758,6 +759,8 @@ static PyMethodDef psycopgMethods[] = {
      METH_VARARGS, psyco_QuotedString_doc},
     {"Boolean",  (PyCFunction)psyco_Boolean,
      METH_VARARGS, psyco_Float_doc},
+    {"Int",  (PyCFunction)psyco_Int,
+     METH_VARARGS, psyco_Int_doc},
     {"Float",  (PyCFunction)psyco_Float,
      METH_VARARGS, psyco_Decimal_doc},
     {"Decimal",  (PyCFunction)psyco_Decimal,
@@ -848,6 +851,7 @@ INIT_MODULE(_psycopg)(void)
     Py_TYPE(&binaryType)     = &PyType_Type;
     Py_TYPE(&isqlquoteType)  = &PyType_Type;
     Py_TYPE(&pbooleanType)   = &PyType_Type;
+    Py_TYPE(&pintType)       = &PyType_Type;
     Py_TYPE(&pfloatType)     = &PyType_Type;
     Py_TYPE(&pdecimalType)   = &PyType_Type;
     Py_TYPE(&asisType)       = &PyType_Type;
@@ -863,6 +867,7 @@ INIT_MODULE(_psycopg)(void)
     if (PyType_Ready(&binaryType) == -1) goto exit;
     if (PyType_Ready(&isqlquoteType) == -1) goto exit;
     if (PyType_Ready(&pbooleanType) == -1) goto exit;
+    if (PyType_Ready(&pintType) == -1) goto exit;
     if (PyType_Ready(&pfloatType) == -1) goto exit;
     if (PyType_Ready(&pdecimalType) == -1) goto exit;
     if (PyType_Ready(&asisType) == -1) goto exit;
@@ -978,6 +983,7 @@ INIT_MODULE(_psycopg)(void)
     binaryType.tp_alloc = PyType_GenericAlloc;
     isqlquoteType.tp_alloc = PyType_GenericAlloc;
     pbooleanType.tp_alloc = PyType_GenericAlloc;
+    pintType.tp_alloc = PyType_GenericAlloc;
     pfloatType.tp_alloc = PyType_GenericAlloc;
     pdecimalType.tp_alloc = PyType_GenericAlloc;
     connectionType.tp_alloc = PyType_GenericAlloc;
diff --git a/psycopg/python.h b/psycopg/python.h
index fed0303e..ed69f4c3 100644
--- a/psycopg/python.h
+++ b/psycopg/python.h
@@ -129,6 +129,7 @@ typedef unsigned long Py_uhash_t;
 #define Bytes_FromString PyString_FromString
 #define Bytes_FromStringAndSize PyString_FromStringAndSize
 #define Bytes_FromFormat PyString_FromFormat
+#define Bytes_ConcatAndDel PyString_ConcatAndDel
 #define _Bytes_Resize _PyString_Resize
 
 #else
@@ -144,6 +145,7 @@ typedef unsigned long Py_uhash_t;
 #define Bytes_FromString PyBytes_FromString
 #define Bytes_FromStringAndSize PyBytes_FromStringAndSize
 #define Bytes_FromFormat PyBytes_FromFormat
+#define Bytes_ConcatAndDel PyBytes_ConcatAndDel
 #define _Bytes_Resize _PyBytes_Resize
 
 #endif
diff --git a/setup.py b/setup.py
index 9ae8117f..bb754116 100644
--- a/setup.py
+++ b/setup.py
@@ -414,7 +414,7 @@ sources = [
 
     'adapter_asis.c', 'adapter_binary.c', 'adapter_datetime.c',
     'adapter_list.c', 'adapter_pboolean.c', 'adapter_pdecimal.c',
-    'adapter_pfloat.c', 'adapter_qstring.c',
+    'adapter_pint.c', 'adapter_pfloat.c', 'adapter_qstring.c',
     'microprotocols.c', 'microprotocols_proto.c',
     'typecast.c',
 ]
@@ -427,7 +427,7 @@ depends = [
 
     'adapter_asis.h', 'adapter_binary.h', 'adapter_datetime.h',
     'adapter_list.h', 'adapter_pboolean.h', 'adapter_pdecimal.h',
-    'adapter_pfloat.h', 'adapter_qstring.h',
+    'adapter_pint.h', 'adapter_pfloat.h', 'adapter_qstring.h',
     'microprotocols.h', 'microprotocols_proto.h',
     'typecast.h', 'typecast_binary.h',
 
diff --git a/tests/types_basic.py b/tests/types_basic.py
index 1ca668de..709907eb 100755
--- a/tests/types_basic.py
+++ b/tests/types_basic.py
@@ -275,6 +275,16 @@ class TypesBasicTests(unittest.TestCase):
         o2 = self.execute("SELECT %s::bytea AS foo", (o1,))
         self.assertEqual(b('x'), o2[0])
 
+    def testNegNumber(self):
+        d1 = self.execute("select -%s;", (decimal.Decimal('-1.0'),))
+        self.assertEqual(1, d1)
+        f1 = self.execute("select -%s;", (-1.0,))
+        self.assertEqual(1, f1)
+        i1 = self.execute("select -%s;", (-1,))
+        self.assertEqual(1, i1)
+        l1 = self.execute("select -%s;", (-1L,))
+        self.assertEqual(1, l1)
+
 
 class AdaptSubclassTest(unittest.TestCase):
     def test_adapt_subtype(self):