TYPO3 Core

If a model holding a DateTime attribute and is filled by a form, currently the error-message for falsely entered values can not be translated because its hard-coded in Extbase's DateTimeConverter.php:169 ( Validation\Error('The date "%s" was not recognized (for format "%s").', 1307719788, [$dateAsString, $dateFormat]) )

The PropertyMapping for this attribute is configured in an initializeAction(), like:

// set input date-format for mapping the user.birthday property
$this->arguments->getArgument('user')->getPropertyMappingConfiguration()
  ->forProperty('birthday')->setTypeConverterOption(
    DateTimeConverter::class,
    DateTimeConverter::CONFIGURATION_DATE_FORMAT,
    'd.m.Y'
);

Input of "test" into the birthday form field resulting in The date "test" was not recognized (for format "d.m.Y"). as non translatable, where as all other messages are in the right locale.