Exchange server 2007, outlook 2007, windows environment w/ Win7x32

Hello all, this is a two-parter

A user at my office is a member of two company domains and would like to view (not necessarily sync) both calendars on one device. For a long time he had been using a Compaq Ipaq H3900 series pocket pc, but this is no longer working. He could just plug it into a computer on one domain, the calendar would sync, then plug it into the other domain and the calendar events from both would layer. Is there another device on which this is possible?

The second part is this: is it possible that an outlook or an exchange update may now be preventing this?

Thanks for any and all help.

-Mike