Well, since you seem to know what you're talking about, you maybe want to help us and provide some well layed out CSS for this case? No redesign of the whole page, just a few lines of CSS that make a line that's 8000-10000 pixels wide appear at a width of 600 pixels without loosing any information (so, shortening the URL is not an option, no "overflow: hidden", etc.). Oh, and no iframes, please. And it has to work in some older IE browsers and FF3 support would be nice too...
I hope this helps:
If the message window is in PHP, the guys of Sophos can integrate a PHP function called wordwrap. It insert a linebreak after a defined amount of characters.
