Why is your site not remapping the tddetails style I would ask. That to me looks strange as tddetails is a normal style used
<table cellpadding="{$Globals['cellpadding']}" cellspacing="0" border="0" bgcolor="{$Globals['framecolor']}">
<tr>
<td>
<table width="100%" cellpadding="0" cellspacing="0" border="0" class="{$Style['tddetails']}">
That is probally what is giving you more black border