<TABLE border="0" cellpadding="0" cellspacing="0">
<TR>
<TD width="9" background="{$ImagesDir}/tab_l.gif"><IMG src="{$ImagesDir}/spacer.gif" width="9" height="1" border="0" alt=""></TD>
<TD height="5" valign="bottom" class="Tab"><IMG src="{$ImagesDir}/spacer.gif" width="1" height="5" border="0" alt=""></TD>
<TD width="9" background="{$ImagesDir}/tab_r.gif"><IMG src="{$ImagesDir}/spacer.gif" width="9" height="1" border="0" alt=""></TD>
</TR>
<TR>
<TD width="9" background="{$ImagesDir}/tab_l.gif"><IMG src="{$ImagesDir}/spacer.gif" width="9" height="1" border="0" alt=""></TD>
<TD width="85" height="30" class="Tab" align="center">{$tab_title}</TD>
<TD width="9" background="{$ImagesDir}/tab_r.gif"><IMG src="{$ImagesDir}/spacer.gif" width="9" height="1" border="0" alt=""></TD>
</TR>
<TR>
<TD width="9" height="9" background="{$ImagesDir}/tab_c1.gif"><IMG src="{$ImagesDir}/spacer.gif" width="9" height="1" border="0" alt=""></TD>
<TD height="9" background="{$ImagesDir}/tab_b.gif"><IMG src="{$ImagesDir}/spacer.gif" width="1" height="9" border="0" alt=""></TD>
<TD width="9" height="9" background="{$ImagesDir}/tab_c2.gif"><IMG src="{$ImagesDir}/spacer.gif" width="9" height="1" border="0" alt=""></TD>
</TR>
</TABLE>
Edited to add:
I can find all those little guys, like "tab_r.gif" in the skin1/images/ directory. The Class=Tab must be where the bulk of the color (outside of those small accent gifs) is located?