Does openfire 3.8.1 with websocket plugin support both httpbind and WS simultaneously?

I update openfire to the version 3.8.1 and add websocket plugin. The websocket functions work fine. But soon I find a problem: the user using http-bind (browser IE9) can’t receive message from the user who is using websocket connection (browser FF). The runtime error and console log on IE9 are:

LOG: 3 : invalid response received

LOG: 3 : responseText:

LOG:

SCRIPT5007: Unable to get value of the property ‘length’: object is null or undefined

strophe.js?_cacheBuster=48, line 688 character 21

I think the problem is the ajax response from xmpp server is wrong. xhr.responseXML.documentElement = null !!!

IS THIS A BUG OR I DID STH WRONG???

CAN ANY1 HELP ME