Remove html tags from t() string

function email_domain_validate_mxr_variable_info($options = array()) {

  $variables['email_domain_validate_mxr_error_message'] = array(

    'title' => t('Email Domain Validate MXR Error Message'),

    'description' => t('Enter !strong_open!email_domain!strong_close where you want to display the offending email domain.',

      array(

        '!strong_open' => '<strong>',

        '!strong_close' => '</strong>',

      )),

    'description' => t('Use token "!email_domain" where you want to display the offending email domain.'),

    'type' => 'string',

    'default' => EMAIL_DOMAIN_VALIDATE_MXR_DEFAULT_ERROR_MESSAGE,

    'localize' => TRUE,