openWithDefaultApplication problem in Flex 3

Hello,

    I am using flex 3 and was previously developing my application with Adobe Air 2.0beta SDK. Today I upgraded my SDK to use Air 2.0 and all of a sudden openWithDefaultApplication is not working anymore. If I point to a File object, the IDE is able to find the method. however, I get the classic

ReferenceError: Error #1069: Property openWithDefaultApplication not found on flash.filesystem.File and there is no default value.

I see that there is a thread about it but no answers unfortunately. I have also updated my (+app.xml to point to adobe AIR 2.0 instead of 2beta.

Any help on this matter will be appreciated.

Thanks,

Ram