See the iPAQ Hardware Compatibility page in the handhelds.org wiki.
No.
16-bit PCMCIA cards (PC Cards) are essentially ISA bus. Cardbus cards are essentially PCI bus. A cardbus socket controller has both an ISA bus and a PCI bus multiplexed onto the same 68 pins of the PCMCIA card. The SA11x0 as well as the Xscale PXA2x0 only support the 16-bit PC Card standard.
If a card is advertised as being cardbus or 32bit, then it it a cardbus card. If it has an extra metal strip with small bumps on the top edge on the end that gets inserted into the PCMCIA socket, then it is a cardbus card.