Date fields don't get saved correctly due to wrong formatting configuration
Currently the date formatting in Typoscript looks for example like this
format.date = %d.%m.%Y
With this formatting the output of a date-field works fine, but it won't get correctly converted back to a timestamp and so it overrides the current value in the database with 0. For correct saving it would need the following TS - but then the output formatting isn't correct.
format.date = d.m.Y
I suggest to change the date formatting option to the one without the % signs and then change the code for displaying the field content from this line ...
$datum = strftime($this->conf['format.']['date'], $arrCurrentData[$fieldName]);
... to this one. Then the code for saving the content in date fields could stay like it is.
$datum = date($this->conf['format.']['date'], $arrCurrentData[$fieldName]);
Updated by Martin Muskulus almost 8 years ago
strftime() - Format a local time/date according to locale settings
date() does not respect locale settings and PHP's documentation recommends
To format dates in other languages, you should use the setlocale() and strftime() functions instead of date().
IMHO typo3 (extensions) should allow for e.g. localized month names.