Date/Time in the manage volunters needs work only in english

At the moment CiviVolunters will pop up a error message stating that "start_time is not a valid date" if we use anything but the event start date/time.

If I change (in the localization setting of CiViCRM) from French(Canada) to English(Canada) or English(United States) IT works fine.

So the "bug" is related to the use of a non-english language (French in my case)