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  $urlsearch[] = "/([^]_a-z0-9-=\"'\/])((https?|ftp):\/\/|www\.)([^ \r\n\(\)\*\^\$!`\"'\|\[\]\{\};<>]*)/si";
  $urlsearch[] = "/^((https?|ftp):\/\/|www\.)([^ \r\n\(\)\*\^\$!`\"'\|\[\]\{\};<>]*)/si";
  $urlreplace[]= "\\1[_URL_]\\2\\4[_/URL_]";
  $urlreplace[]= "[_URL_]\\1\\3[_/URL_]";

  $emailsearch[] = "/([\s])([_a-zA-Z0-9-]+(\.[_a-zA-Z0-9-]+)*@[a-zA-Z0-9-]+(\.[a-zA-Z0-9-]+)*(\.[a-zA-Z]{2,}))/si";
  $emailsearch[] = "/^([_a-zA-Z0-9-]+(\.[_a-zA-Z0-9-]+)*@[a-zA-Z0-9-]+(\.[a-zA-Z0-9-]+)*(\.[a-zA-Z]{2,}))/si";
  $emailreplace[]= "\\1[_MAIL_]\\2[_/MAIL_]";
  $emailreplace[]= "[_MAIL_]\\0[_/MAIL_]";

  $text = preg_replace($urlsearch, $urlreplace, $text);