TYPO3 Core

I have an extbase extension with model and repository. When I try to update an entry via extbase repositiory update() function it fails as soon as there are special umlauts in the entry.

When I overwrite the update() function in my repository and update the entry via GLOBAL_DB->execUPDATEquery it works. The field/column with the umlauts is of type varchar.

In my opinion either extbase repsitory or at the end DBAL does not respect/convert umlauts in the update.

By the way: When the update fails, a new entry is created. The add() function seems not to have the problem with umlauts...