ical download issue

Hello I get the following error when I try and download the calendar.

http://localhost:8080/calendarmodule/calendar-created/ical/2012-05/calen...

Error

The website encountered an unexpected error. Please try again later.
Error messageException: DateTimeZone::__construct() [datetimezone.--construct]: Unknown or bad timezone (1) in DateTimeZone->__construct() (line 203 of D:\wamp\www\calendarmodule\sites\all\modules\date\date_api\date_api.module).