well I did find this module that looks like the once that needs to be modifed
PHP Code:
<plugin active="1" product="fsvpboupc">
<title><![CDATA[Cyb - APBOUPC - P5 (SR)]]></title>
<hookname>parse_templates</hookname>
<phpcode><![CDATA[
if ($vbulletin->options['apboupc_global_enable'] AND ($vbulletin->options['apboupc_pm_amount']>0) AND (THIS_SCRIPT=='private'))
{
if (($vbulletin->options['apboupc_pm_amount'] !='0') AND ($vbulletin->options['apboupc_pm_amount'] > $vbulletin->userinfo[posts]) AND (!is_member_of($vbulletin->userinfo, split(',', $vbulletin->options['apboupc_pm_excludedgroups']))))
{
$apboupc_pmsnote = construct_phrase($vbphrase['apboupc_pm_note'], $vbulletin->options['apboupc_pm_amount']);
$vbulletin->templatecache['pm_newpm'] = str_replace('$vbphrase[separate_multiple_names]', '$vbphrase[separate_multiple_names]<br /><br />$apboupc_pmsnote', $vbulletin->templatecache['pm_newpm']);
}
}]]></phpcode>
</plugin>