diff --git a/httplib2/socks.py b/httplib2/socks.py
index 6f4f020..b65fb38 100644
--- a/httplib2/socks.py
+++ b/httplib2/socks.py
@@ -41,12 +41,13 @@
 """
 
 import socket
+
+if getattr(socket, 'socket', None) is None:
+    raise ImportError('socket.socket missing, proxy support unusable')
+
 import struct
 import sys
 
-if not hasattr(socket, 'socket'):
-  raise ImportError("Running on App Engine?")
-
 PROXY_TYPE_SOCKS4 = 1
 PROXY_TYPE_SOCKS5 = 2
 PROXY_TYPE_HTTP = 3