How to create /dev/dsp ?

[Timothy Murphy]

I took a disk out of one computer, and put it in another
(more precisely, I took out the Utrabay hard disk from a ThinkPad T20
and put it in a ThinkPad T23)
and now I am told there is no sound because
"Device /dev/dsp does not exist".

How exactly does one ensure that this device is created?
There seems to be a rule in /etc/udev/rules.d/
        KERNEL=="dsp*",                 MODE="0660"
I take it this just says that if /dev/dsp is created 
it should have mode 0660?

I googled quite extensively for "fedora udev dsp"
and came across a large number of queries
and a few answers which I tried without success.
Several referred to "alsaconf" which does not seem to be available in FC-5.

I seem to have modules running which should create /dev/dsp ,
as shown by the partial lsmod list below.

I'd be very grateful for a solution to this conundrum:
how do I create /dev/dsp, and why has it not been created for me?

---------------------------------------
snd_emu10k1_synth       6464  0
snd_emux_synth         32032  1 snd_emu10k1_synth
snd_seq_virmidi         5120  1 snd_emux_synth
snd_seq_midi_emul       5888  1 snd_emux_synth
snd_emu10k1           114180  1 snd_emu10k1_synth
snd_rawmidi            18912  2 snd_seq_virmidi,snd_emu10k1
snd_ac97_codec         92032  1 snd_emu10k1
snd_ac97_bus            1792  1 snd_ac97_codec
snd_seq_oss            29888  0
snd_seq_midi_event      5888  2 snd_seq_virmidi,snd_seq_oss
snd_seq                45744  7
snd_emux_synth,snd_seq_virmidi,snd_seq_midi_emul,snd_seq_oss,snd_seq_midi_event
snd_pcm_oss            34624  0
snd_mixer_oss          15424  1 snd_pcm_oss
snd_pcm                65640  3 snd_emu10k1,snd_ac97_codec,snd_pcm_oss
snd_seq_device          6348  6
snd_emu10k1_synth,snd_emux_synth,snd_emu10k1,snd_rawmidi,snd_seq_oss,snd_seq
snd_timer              18180  3 snd_emu10k1,snd_seq,snd_pcm
snd_page_alloc          7656  2 snd_emu10k1,snd_pcm
snd_util_mem            3328  2 snd_emux_synth,snd_emu10k1
snd_hwdep               6660  2 snd_emux_synth,snd_emu10k1
snd                    42916  13
snd_emux_synth,snd_seq_virmidi,snd_emu10k1,snd_rawmidi,snd_ac97_codec,snd_seq_oss,snd_seq,snd_pcm_oss,snd_mixer_oss,snd_pc
---------------------------------------

Incidentally, is there any way of re-starting the sound system
apart from re-booting?
Why can one not say "system sound restart"?

-- 
Timothy Murphy  
e-mail (<80k only): tim /at/ birdsnest.maths.tcd.ie
tel: +353-86-2336090, +353-1-2842366
s-mail: School of Mathematics, Trinity College, Dublin 2, Ireland