diff --git a/mitogen/compat/pkgutil.py b/mitogen/compat/pkgutil.py
index 28e2aeade..df3983a2b 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:
diff --git a/mitogen/master.py b/mitogen/master.py
index 48f82ab17..814f7019b 100644
--- a/mitogen/master.py
+++ b/mitogen/master.py
@@ -462,7 +462,7 @@ def find(self, fullname):
             return None
 
         path = getattr(mod, '__file__', None)
-        if not (os.path.exists(path) and _looks_like_script(path)):
+        if not (path is not None and os.path.exists(path) and _looks_like_script(path)):
             return None
 
         fp = open(path, 'rb')
diff --git a/mitogen/parent.py b/mitogen/parent.py
index 99d8d6216..79b484c2a 100644
--- a/mitogen/parent.py
+++ b/mitogen/parent.py
@@ -2331,7 +2331,7 @@ def disconnect(self, context):
         directly connected.
         """
         stream = self.stream_by_id(context)
-        if stream.remote_id != context.context_id:
+        if stream.protocol.remote_id != context.context_id:
             return
 
         l = mitogen.core.Latch()