I had teh same issue where I had one more extra field other tham username and password.
I tried few things but was not able to get the extra field info at my LoginModule.
Not sure if this is helpful but this is how I did it in my applications
thanks for your help.
This solution I've read allready in other forum. But for our project this solution will not be accept. I hope developers from JBoss must known how to solve this problem.