Index: Lib/zipfile.py
===================================================================
--- Lib/zipfile.py	(revision 74955)
+++ Lib/zipfile.py	(working copy)
@@ -351,9 +351,14 @@
 
     def _decodeFilename(self):
         if self.flag_bits & 0x800:
-            return self.filename.decode('utf-8')
+            fname = self.filename.decode('utf-8')
         else:
-            return self.filename
+            fname = self.filename
+        # Ensure forward slashes as stated in the standard, in case the
+        # compressor did this minor error.
+        if '\\' in fname:
+            fname = fname.replace('\\', '/')
+        return fname
 
     def _decodeExtra(self):
         # Try to decode the extra field.
@@ -767,6 +772,10 @@
             if self.debug > 2:
                 print centdir
             filename = fp.read(centdir[_CD_FILENAME_LENGTH])
+            # Ensure forward slashes as stated in the standard, in case the
+            # compressor did this minor error.
+            if '\\' in filename:
+                filename = filename.replace('\\', '/')
             # Create ZipInfo instance to store file information
             x = ZipInfo(filename)
             x.extra = fp.read(centdir[_CD_EXTRA_FIELD_LENGTH])
@@ -879,6 +888,10 @@
         fname = zef_file.read(fheader[_FH_FILENAME_LENGTH])
         if fheader[_FH_EXTRA_FIELD_LENGTH]:
             zef_file.read(fheader[_FH_EXTRA_FIELD_LENGTH])
+        # Ensure forward slashes as stated in the standard, in case the
+        # compressor did this minor error.
+        if '\\' in fname:
+            fname = fname.replace('\\', '/')
 
         if fname != zinfo.orig_filename:
             raise BadZipfile, \