6.0-RC1 hostapd with wi(4) problems

I have FreeBSD 6.0-RC1 setup as an AP using ath(4) driver,
hostapd(8) using WPA-PSK, and if_bridge(4) between an sis(4)
and wi(4). It seems to work well with a windows XP client.

When I try to substitute the wi(4) driver (with card firmware 1.7.4)
windows XP seems to see it to be WEP security rather than AES,TKIP
and will not associate.

Running hostapd with debugging seem to indicate no packets are
passed to hostapd and I do not see received packet on the wi(4)
interface with netstat -i.

With open authentication wi(4) seems to work well.

Is there something different in capabilities between the ath(4)
and wi(4) drivers related to using hostapd in FreeBSD?

The intersil-prism card I have used with hostapd in linux for
over a year with no problems.