ganzua, can you post a link to your forum so we can take a look at the html/css?
Also, to get both IE6 and IE7 on the same Windows machine, check this out:
* http://tredosoft.com/Multiple_IE
I have it installed on this machine, and it’s fantastic and very stable.
As fel64 notes, max-width works well in FF and IE7. However, since max-width may have problems in IE6, you may want to try this alternate CSS:
.authorlist {
width: 75px;
overflow: hidden;
}