Check for city email during registration

gistfile1.aw

<?php
/** 
 *	Check for City Email
 *
 *	If a user tries to register with a city email address an error is returned.
 *
 *	@author		Nate Jacobs
 *	@link		http://gist.github.com/1257325
 */
add_action( 'registration_errors', 'check_user_email',10, 3 );

function check_user_email( $errors, $login, $email )
{
	list( $addy, $domain ) = explode( "@", $email );
	
	if ( $domain == 'chandleraz.gov' )
	{
		$errors->add('empty_realname', __( '<strong>City Email Alert: </strong><br>No @chandleraz.gov email addresses allowed.' ) );
	}
	
	return $errors;
}
?>