no sound from the speakers of your T60/x60? Turn on the Modem!!!

Gah!
Not sure who's fault this strange problem is, but it is realy hard to catch, and I fiddled and googled quite some time for it...

For one, when playing sound on the command line, I've got

ALSA lib pcm_direct.c:867snd_pcm_direct_initialize_slave) snd_pcm_hw_params_any failed
ALSA lib pcm_dmix.c:876snd_pcm_dmix_open) unable to initialize slave
aplay: main:545: audio open error: Invalid argument

and xmms said something about the audio device not available.
Googling for others who had this problem, too, I only found things like this (which, in the meantime also contains a post of mine pointing to the real solution, but at that time didn't).
Only when I figured to look up some errors in dmesg output, namely

hda_intel: azx_get_response timeout, switching to polling mode…
hda_intel: azx_get_response timeout, switching to single_cmd mode…

and googled for this, I finally found a solution... you have to enable the MODEM on a (t60, X60, and others...) thinkpad, to get sound out of your SPEAKERS!!!

Sounds clearly logical... to someone with a twisted brain...
If this is not a drover bug, the BIOS should warn peopl to remind them, if the switch the modem to "hidden", they won't be able to listen to music, too.