Importing a csv-file with a duedate is not possible as a project admin

Trying to import a csv-file as a project administrator with a given duedate results in a validator error.

The validation process has found 1 error/s
•Issue can't be created due to the error/s [ You did not enter a valid date. Please enter the date in the format "dd.MM.yyyy", eg. "25.11.2014" ]

Importing the same csv-file with the same configuration as a system administrator succeeds (see log.txt)

Can you please verify this problem.