IE8 and phpFreeChat (the underlying chat script in jPFChat) have some compatibility issues.

The main problem is a display issue where the userlist (far right side of the chat window) doesn't display where it's supposed to.  Instead, it overwrites the screen on the left side, at the bottom of the chat window.

The WORKAROUND... tell your IE8 users to turn ON the IE7 Compatibility Mode.  They can do this simply by clicking the little broken window icon just to the right of their browser URL navigation box.

UPDATE...  The v2 Stable release WILL have a workaround that Forces the jPFChat page to load into an IE7 compatibile mode in IE8 browsers.  The v2 Stable release should occur in late April (hopefully before May 1).