please excuse my newbie question. I am wondering if it is possible to pass along the user's login credentials to a webserver that he is accessing. Is this possible? What needs to be done?
yes it is.
You got several possibilities to solve it, e.g. by a post request or by adding data to the http header.
More can be found in the Admindocs or in the onlinehelp of the IVE or here: http://kb.pulsesecure.net/kb/documents/public/IVE/SA-SM-Admin-Help/wwhelp/wwhimpl/common/html/wwhelp.htm?context=SA_Admin_Help&file=chapWebRewriting-05.html
EDIT: Sry, link corrected. Just took the link to this onelinehelp from the WSAM thread and forgot about the frames