src/Service/validateService.php
public function strongPassword($value)
    {
        $this->errorMessage = null;
        require_once 'Zend/Validate/Regex.php';
        $validator = new \Zend_Validate_Regex("/^.*(?=.{8,})(?=.*\d)(?=.*[a-z])(?=.*[A-Z]).*$/");
        $result = $validator->isValid($value);
        if (!$result) {
            $this->errorMessage = MessageHelper::getMessage("VALIDATESVC_PASSWORD_NOT_STRONG", array($this->fieldNameMask));
        }
        return $result;
    }
public function strongPassword($value)
    {
        $this->errorMessage = null;
        require_once 'Zend/Validate/Regex.php';
        $validator = new \Zend_Validate_Regex("/^.*(?=.{8,})(?=.*\d)(?=.*[a-z])(?=.*[A-Z]).*$/");
        $result = $validator->isValid($value);
        if (!$result) {
            $this->errorMessage = MessageHelper::getMessage("VALIDATESVC_PASSWORD_NOT_STRONG", array($this->fieldNameMask));
        }
        return $result;
    }
Strong Password checks if the string is "strong", i.e. the password must be at least 8 characters
and must contain at least one lower case letter, one upper case letter and one digit

@param mixed $value
@return boolean Valid?