problem with email from app

  
function send_email($to, $fromaddr, $fromname, $subject, $message_text, $message_html = "")   
{   
  $subject = preg_replace("/\nfrom\:.*?\n/i", "", $subject);   
  $subject = preg_replace("/\nbcc\:.*?\n/i", "", $subject);   
  $subject = preg_replace("/\ncc\:.*?\n/i", "", $subject);   
  $message_text = preg_replace("/\nfrom\:.*?\n/i", "", $message_text);   
  $message_text = preg_replace("/\nbcc\:.*?\n/i", "", $message_text);   
  $message_text = preg_replace("/\ncc\:.*?\n/i", "", $message_text);   
  $message_html = preg_replace("/\nfrom\:.*?\n/i", "", $message_html);   
  $message_html = preg_replace("/\nbcc\:.*?\n/i", "", $message_html);   
  $message_html = preg_replace("/\ncc\:.*?\n/i", "", $message_html);   
  
  // create additional_parameters - this ensures that the RETURN-PATH will be properly set   
  // saving the mail from being rejected by the destination mail server as spam   
  // known servers that reject if RETURN-PATH domain does not match the from domain include   
  // gmail, hotmail, aol, excite, yahoo, btinternet   
  // most spam killers will also regard emails with   
  $additional_parameters = "-f $fromaddr";   
  
  // create additional_headers   
  $headers = "From: $fromname <$fromaddr>\r\n";   
  
  // specify MIME version 1.0   
  $headers .= "MIME-Version: 1.0\r\n";   
  
  // deal with html messages   
  if($message_html != "")   
  {   
   // unique boundary   
   $boundary =  md5(uniqid(time()));  //uniqid("sometext");   
  
   // tell e-mail client this e-mail contains alternate versions   
   $headers .= "Content-Type: multipart/alternative; boundary = $boundary\r\n\r\n";   
  
   // plain text version of message   
   $body  = "--$boundary\r\n";   
   $body .= "Content-Type: text/plain; charset=ISO-8859-1\r\n";   
   $body .= "Content-Transfer-Encoding: 7 bit\r\n\r\n";   
   $body .= $message_text."\r\n\r\n";   
  
   // HTML version of message   
   $body .= "--$boundary\r\n";   
   $body .= "Content-Type: text/html; charset=ISO-8859-1\r\n";   
   $body .= "Content-Transfer-Encoding: 7 bit\r\n\r\n";   
   $body .= $message_html."\r\n\r\n";   
  }   
  
  // deal with plain text only messages   
  if($message_html == "")   
  {   
   // tell e-mail client the content type   
     $headers .= "Content-type: text/plain; charset=iso-8859-1\n";   
  
   // the plain text message   
   $body = $message_text;   
  }   
  
  // send message   
  return mail($to, $subject, $body, $headers, $additional_parameters);   
}