clients don't boot

[dbclinton]

I've just had to reinstall edubuntu 10.04 manually via ltsp-build-client
(there was some bug that was crashing my system three or four times a
day that I just couldn't diagnose) and, because of my proxy server, I
had to reinstall ltsp separately (thanks to Scott B.'s advice). This
time, however, the server doesn't seem to be giving out ip addresses to
the clients ("no dhcp offers"). Nothing is showing up on daemon.log or
syslog. ifconfig tells me that eth1 is at 192.168.0.254, 255.255.255.0 -
I've tried letting network-manager manage eth1 (it does take it
successfully, leaving 192.168.0.254, but still doesn't help for ltsp)
What am I doing wrong?
Thanks