JAP session problem

[kahless]

I am having problems with gettin a session to work on JSP using
TOMCAT. I have set <%@ Page session = "true" %> at the start, but then
later when I use:

session.setAttribute("usrname", "usrname")

I get an Invalid type expression error.

I don't think I need to use HttpSession as I have already set the
session to true, and when I do it throws up something like it's
already defined.

Thanks for any help