Problem accessing specific site through ISA server

From: aid.roberts (aid.roberts_at_blueyonder.co.uk)
Date: 09/08/04 

Date: 8 Sep 2004 04:39:34 -0700

We are having problems accessing one specific site. When browsing
there are errors on page, and most pages display garbled text. Bypass
the ISA and the site can be accessed fine. Any ideas?

Many thanks