Thread:Project:Support desk/Adress confirmation does not work anymore with MW 1.20.1

Yesterday I have updated my Wiki from 1.15.x to the new version 1.20.1

-> Everything works fine except the e-mail adress confirmation. If I register myself as a new user I get a e-mail with a confirmation link, but if I click on this link I get the following error message:

"Ungültiger Bestätigungscode. Möglicherweise ist der Bestätigungszeitraum verstrichen. Versuche bitte, die Bestätigung zu wiederholen." (Translation: Confirmation code not valid. Timeout - please try to repeat the confirmation.")

The PHP Version is 5.3.8.

Any thoughts about this behavior?