email_valid function not working??

hi. thanks in advance for any help! i'm trying to make the email_valid function that i found on php.net work. i can get it to validate the email formatting, but it always fails on the MX check and the DNS check. any ideas??? thanks! please cc ben@akimbodesign.com with any answers function valid_email ($email) { if (eregi("^[0-9a-z_]([-_.]?[0-9a-z])*@[0-9a-z]([-.]?[0-9a-z])*\\.[a-z]{2,3}$", $email,$check)) { echo "passed formatting test. "; if ( getmxrr(substr(strstr($check[0], '@'), 1), $validate_email_temp) ) { echo "passed getmxrr test. "; return TRUE; } // THIS WILL CATCH DNSs THAT ARE NOT MX. if(checkdnsrr(substr(strstr($check[0], '@'), 1),"ANY")){ echo "passed dns check"; return TRUE; } } echo "FALSE<BR>"; return FALSE; }