Jaas on jboss integration

Hello,

I'm trying to integrate spring security for two web application on Jboss. I'm using FORM authentication with JAAS realm. I have also enabled simple single sign on provided by jboss (org.apache.catalina.authenticator.SingleSignOn).
Now i want to introduce spring security and initialize security context with principal provided by jboss JAAS mechanism. If i use preAuthentication, the filter is invoked before HTTP request is populated with principal obtained from JAAS form login. If i use spring form login instead of Jboss JAAS, then SSO doesn't work.
Does someone have experience with this kind of integration?

Thanks.