Post as someone else, getting usernametaken error when trying to post

[Sarteck]

I'm designing a "Puppet" system that will allow some users to post as another account. I'm having a bit of trouble, though.

I get the usernametaken error each time I post, but I don't really see why.



on newpost_process (only enclosed by the outer IF block for testing).

PHP Code:

if ($vbulletin->userinfo['userid'] == [MYUSERID])
{



$persona_id = $vbulletin->input->clean_gpc('p', 'persona_id', TYPE_UINT); 
if ($persona_id && ($vbulletin->userinfo['userid'] != $persona_id))  // If "persona_id" is set from form data AND the persona ID is not the UserID
{
  require_once(DIR . '/includes/functions_cbps.php');
  $personas = get_personas($vbulletin->userinfo['userid']);
  if ($personas && (in_array($persona_id, $personas))) // If this user has personas, AND the persona they are trying to post as does indeed belong to them, then continue.
  {
    $persona = fetch_persona($persona_id); // Gets the UserInfo of a persona given an ID.
    $dataman->set('username',$persona['username']);
    $dataman->set('userid',$persona['userid']);
  }
  else
  {
    standard_error('You seem to be trying to post as a Persona that doesn\'t belong to you.', false);
  }
}


} 


It is getting the persona info fine, but setting the userid and username fields of the post seems to give it a heart attack or something.

Is there some permissions things I have to muck around with? I basically want to enable the ability to post with a persona using the forum permissions of the logged-in user. (Later, before I release it, I'll be restricting it to just a few forums.)




Anyways, could anyone point me in the right direction?