diff --git a/PIL/Image.py b/PIL/Image.py
index 6470d0155..27acc8500 100644
--- a/PIL/Image.py
+++ b/PIL/Image.py
@@ -616,11 +616,7 @@ class Image:
             self.palette.mode = "RGB"
             self.palette.rawmode = None
             if "transparency" in self.info:
-                if self.info["transparency_palette"]:
-                    self.im.putpalettealpha(0, 0, self.info["transparency_palette"])
-                else:
-                    self.im.putpalettealpha(self.info["transparency"], 0)
-
+                self.im.putpalettealpha(self.info["transparency"], 0)
                 self.palette.mode = "RGBA"
         if self.im:
             return self.im.pixel_access(self.readonly)
diff --git a/PIL/PngImagePlugin.py b/PIL/PngImagePlugin.py
index 80757fc9b..0eee64942 100644
--- a/PIL/PngImagePlugin.py
+++ b/PIL/PngImagePlugin.py
@@ -254,7 +254,6 @@ class PngStream(ChunkStream):
             i = s.find(b"\0")
             if i >= 0:
                 self.im_info["transparency"] = i
-                self.im_info["transparency_palette"] = s
         elif self.im_mode == "L":
             self.im_info["transparency"] = i16(s)
         elif self.im_mode == "RGB":
diff --git a/_imaging.c b/_imaging.c
index 8ebaad52b..6bf3fe598 100644
--- a/_imaging.c
+++ b/_imaging.c
@@ -741,13 +741,13 @@ _convert(ImagingObject* self, PyObject* args)
 	return NULL;
     if (paletteimage != NULL) {
       if (!PyImaging_Check(paletteimage)) {
-        PyObject_Print((PyObject *)paletteimage, stderr, 0);
-        PyErr_SetString(PyExc_ValueError, "palette argument must be image with mode 'P'");
-        return NULL;
+	PyObject_Print((PyObject *)paletteimage, stderr, 0);
+	PyErr_SetString(PyExc_ValueError, "palette argument must be image with mode 'P'");
+	return NULL;
       }
       if (paletteimage->image->palette == NULL) {
-        PyErr_SetString(PyExc_ValueError, "null palette");
-        return NULL;
+	PyErr_SetString(PyExc_ValueError, "null palette");
+	return NULL;
       }
     }
 
@@ -1415,9 +1415,7 @@ _putpalettealpha(ImagingObject* self, PyObject* args)
 {
     int index;
     int alpha = 0;
-    char* tpalette = NULL;
-    int tpaletteSize = 0;
-    if (!PyArg_ParseTuple(args, "i|i"PY_ARG_BYTES_LENGTH, &index, &alpha, &tpalette, &tpaletteSize))
+    if (!PyArg_ParseTuple(args, "i|i", &index, &alpha))
 	return NULL;
 
     if (!self->image->palette) {
@@ -1429,17 +1427,9 @@ _putpalettealpha(ImagingObject* self, PyObject* args)
 	PyErr_SetString(PyExc_ValueError, outside_palette);
 	return NULL;
     }
-    
-    strcpy(self->image->palette->mode, "RGBA");
 
-    if (tpaletteSize > 0) {
-        for (index = 0; index < tpaletteSize; index++) {
-            self->image->palette->palette[index*4+3] = (UINT8) tpalette[index];
-        }
-    }
-    else {
-        self->image->palette->palette[index*4+3] = (UINT8) alpha;
-    }
+    strcpy(self->image->palette->mode, "RGBA");
+    self->image->palette->palette[index*4+3] = (UINT8) alpha;
 
     Py_INCREF(Py_None);
     return Py_None;
@@ -3409,4 +3399,3 @@ init_imaging(void)
 }
 #endif
 
-
diff --git a/selftest.py b/selftest.py
index f0cbe0ba4..01c78a3ff 100644
--- a/selftest.py
+++ b/selftest.py
@@ -157,7 +157,7 @@ def testimage():
 
 def check_module(feature, module):
     try:
-        __import__(module)
+        __import__("PIL." + module)
     except ImportError:
         print("***", feature, "support not installed")
     else: