diff --git a/sleekxmpp/basexmpp.py b/sleekxmpp/basexmpp.py
index bfbfd594..2c2bb91e 100644
--- a/sleekxmpp/basexmpp.py
+++ b/sleekxmpp/basexmpp.py
@@ -122,7 +122,7 @@ class basexmpp(object):
                 # threaded is no longer needed, but leaving it for backwards compatibility for now
 		if name is None:
 			name = 'add_handler_%s' % self.getNewId()
-        	self.registerHandler(XMLCallback(name, MatchXMLMask(mask), pointer, threaded, disposable, instream))
+		self.registerHandler(XMLCallback(name, MatchXMLMask(mask), pointer, threaded, disposable, instream))
 	
 	def getId(self):
 		return "%x".upper() % self.id