PCMCIA: The Type III slot can accommodate two Type I or two Type II,
or one Type III PC card. Both 16-bit and 32-bit cards are supported.
Both PCMCIA slots contain a ZV port. PC Card Support Software: The
auto configurator and memory device driver enable supported PCMCIA
cards by sensing them automatically. PCMCIA cards supported by the
auto configurator and memory device driver are listed in the Sales
Manual.

As they mention 32-bit cards, they must be implying CardBus, no? the
following c|net review states CardBus explicitly:

http://reviews.cnet.com/laptops/thinkpad-a22m-p3-900/1707-3121_7-5600308.html