diff --git a/mitogen/compat/pkgutil.py b/mitogen/compat/pkgutil.py
index 28e2aead..df3983a2 100644
--- a/mitogen/compat/pkgutil.py
+++ b/mitogen/compat/pkgutil.py
@@ -542,7 +542,7 @@ def extend_path(path, name):
         if os.path.isfile(pkgfile):
             try:
                 f = open(pkgfile)
-            except IOError, msg:
+            except IOError as msg:
                 sys.stderr.write("Can't open %s: %s\n" %
                                  (pkgfile, msg))
             else: