I got sound working in FreeBSD 5.0-CURRENT on this thing
(a Dell Latitude CPi D300XT) with the following:

in kernel config:
device pcm

in /boot/device.hints:
hint.pcm.0.port="0x52c"
hint.pcm.0.at="isa"
hint.pcm.0.irq="5"
hint.pcm.0.drq="1"
hint.pcm.0.flags="0x10"