--- a/rollbot.py	Wed May 11 00:09:34 2016 +0800
+++ b/rollbot.py	Wed May 11 14:43:23 2016 +0800
@@ -36,7 +36,12 @@
         if msg['type'] not in ('chat', 'normal'):
             return
 
-        rbody = self.respond(msg['body'].strip())
+        mbody = msg['body'].lstrip()
+        if mbody.startswith(self.prefix):
+            mbody = mbody[len(self.prefix):]
+
+        mbody = mbody.lstrip(' ')
+        rbody = self.respond(mbody)
         if rbody:
             msg.reply(rbody)
             msg.send()
@@ -53,7 +58,7 @@
         else:
             return
 
-        mbody = mbody.lstrip(':, \t')
+        mbody = mbody.lstrip(':, ')
         rbody = self.respond(mbody)
         if rbody:
             rbody = '%s: %s' % (msg['mucnick'], rbody)