"'%value%' has not only hexadecimal digit characters" ); /** * Defined by Zend_Validate_Interface * * Returns true if and only if $value contains only hexadecimal digit characters * * @param string $value * @return boolean */ public function isValid($value) { $valueString = (string) $value; $this->_setValue($valueString); if (!ctype_xdigit($valueString)) { $this->_error(); return false; } return true; } }