google calendars on iphone

For historical reasons I use extensively the Google calendar. Google offers among others a birthday calendar for the contacs saved in google. I have also created a separate Google calendar for my work.

I can make all 3 calendars visible in iCal on Lion, using the accounts settings.

This seems not to be possible (any more?) on the iPhone (iOS 5.x), where just the main personal Google calendar will be accessed.

Is this a bug or a feature? :-)

Regards,

Andre