Try looping until you get the end.
on *:sockread:creds.*: {
 sockread &data
 if ($bfind(&data, 1, BinarySecurityToken Id="PPToken1">t=)) {
  ;...append original line
  while (!$bfind(&data, %start,  </wsse:BinarySecurityToken>)) {
   ;...append data
   sockread &data
  ;...There'll be some data at the end, append it too.

One problem is the length by which the loop may run maybe freezing up mIRC, make sure you don't let it run forever.
Sorry if that's bad psuedocode =(

Last edited by Firstmate; 03/06/10 04:33 AM.