Viewing source on the page gave me the following html for the post icon table cell:
<td class="ev_msg_posticon">
Playing around in Top Style Pro gave me this (JC jump in if I'm wrong):
.test {<br /> border-left: 1px solid Black;<br /> border-bottom: 1px solid Black; <br /> border-top: solid 1px Black; <br /> } You could change "test" to anything you want and then apply it to the table cell that holds the post icon in the showflat and showthreaded scripts -not too easy cause there is a lot more than just the post icon in that table cell. Look for this in the showflat.tmpl file:
<td align="left" width="70%" valign="top"><br /><img src="{$config['images']}/icons/{$postrow[$i]['Icon']}" {$images['icons']} alt="" $imagestyle /> Then you'd have to come up with another class for the bottom border after the post icon. Not a simple task, but not too tough
P.S. I have no time to get into another template mod right now -I'm knee deep into scripting Facelift for Threads 6.5
