diff --git a/psycopg/cursor_type.c b/psycopg/cursor_type.c
index effb2e66..b65b7d22 100644
--- a/psycopg/cursor_type.c
+++ b/psycopg/cursor_type.c
@@ -1028,8 +1028,6 @@ psyco_curs_callproc(cursorObject *self, PyObject *args)
     int using_dict;
 #if PG_VERSION_HEX >= 0x090000
     PyObject *pname = NULL;
-    PyObject *spname = NULL;
-    PyObject *bpname = NULL;
     PyObject *pnames = NULL;
     char *cpname = NULL;
     char **scpnames = NULL;
@@ -1076,37 +1074,24 @@ psyco_curs_callproc(cursorObject *self, PyObject *args)
         for (i = 0; i < nparameters; i++) {
             /* all errors are RuntimeErrors as they should never occur */
 
-            if (!(pname = PyList_GetItem(pnames, i))) {
+            if (!(pname = PyList_GetItem(pnames, i))) { goto exit; }
+            Py_INCREF(pname);   /* was borrowed */
+
+            /* this also makes a check for keys being strings */
+            if (!(pname = psycopg_ensure_bytes(pname))) { goto exit; }
+            if (!(cpname = Bytes_AsString(pname))) { goto exit; }
+
+            if (!(scpnames[i] = PQescapeIdentifier(
+                    self->conn->pgconn, cpname, strlen(cpname)))) {
                 goto exit;
             }
 
-            if (!(spname = PyObject_Str(pname))) {
-                goto exit;
-            }
-
-            /* this is the only function here that returns a new reference */
-            if (!(bpname = psycopg_ensure_bytes(spname))) {
-                goto exit;
-            }
-
-            if (!(cpname = Bytes_AsString(bpname))) {
-                Py_XDECREF(bpname);
-                goto exit;
-            }
-
-            if (!(scpnames[i] = PQescapeIdentifier(self->conn->pgconn, cpname,
-                        strlen(cpname)))) {
-                Py_XDECREF(bpname);
-                goto exit;
-            }
-
-            Py_XDECREF(bpname);
+            Py_CLEAR(pname);
 
             sl += strlen(scpnames[i]);
         }
 
-        sql = (char*)PyMem_Malloc(sl);
-        if (sql == NULL) {
+        if (!(sql = (char*)PyMem_Malloc(sl))) {
             PyErr_NoMemory();
             goto exit;
         }
@@ -1170,6 +1155,7 @@ exit:
         }
     }
     PyMem_Del(scpnames);
+    Py_XDECREF(pname);
     Py_XDECREF(pnames);
 #endif
     Py_XDECREF(operation);
diff --git a/tests/test_cursor.py b/tests/test_cursor.py
index 00d19dfb..00143ee9 100755
--- a/tests/test_cursor.py
+++ b/tests/test_cursor.py
@@ -520,9 +520,9 @@ class CursorTests(ConnectingTestCase):
             ({ paramname: 2, 'foo': 'bar' }, psycopg2.ProgrammingError),
             ({ paramname: '2' },             psycopg2.ProgrammingError),
             ({ paramname: 'two' },           psycopg2.ProgrammingError),
-            ({ 'bjørn': 2 },                 psycopg2.ProgrammingError),
-            ({ 3: 2 },                       psycopg2.ProgrammingError),
-            ({ self: 2 },                    psycopg2.ProgrammingError),
+            ({ u'bj\xc3rn': 2 },             psycopg2.ProgrammingError),
+            ({ 3: 2 },                       TypeError),
+            ({ self: 2 },                    TypeError),
         ]
         for parameter_sequence, exception in failing_cases:
             self.assertRaises(exception, cur.callproc, procname, parameter_sequence)