[Freesteyelz]

Yup, you got it. The image won't dynamically resize the picture in the way you probably want. If anything it'll go along the dimensions of the <td> or <div> setting you lay out in the templates. In the postbit template you'll probably see this (on a default template):

			<if condition="$show['avatar']"><td class="alt2"><a href="member.php?$session[sessionurl]u=$post[userid]"><img src="$post[avatarurl]" $post[avwidth] $post[avheight] alt="<phrase 1="$post[username]">$vbphrase[xs_avatar]</phrase>" border="0" /></a></td></if>

Replace it with:

			<if condition="$show['avatar']"><td class="alt2"><a href="member.php?$session[sessionurl]u=$post[userid]"><img src="$post[avatarurl]" width="100px" height="100px" alt="<phrase 1="$post[username]">$vbphrase[xs_avatar]</phrase>" border="0" /></a></td></if>

Adjust the "width" and "height" settings to whatever you want.

I know this isn't what you wanted exactly but for me if I can avoid messing with the PHP files I'll do so. However, if this solution is not what you want then I would make a request in either the Service or Unpaid Modification forums.