My Powerbook 3400 I got on Ebay for $100 works great with linux, except 
that the sound driver which worked in 2.6.8 now oopses on modprobe in 
both 2.6.12-rc3 and 2.6.12-rc3-mm2. The oops looks like this:

Oops: kernel access of bad area, sig: 11 [#1]
PREEMPT
NIP: C62CC038 LR: C6238BCC SP: C4133E70 REGS: c4133dc0 TRAP: 0300    Not 
tainted
MSR: 00009032 EE: 1 PR: 0 FP: 0 ME: 1 IR/DR: 11
DAR: 00000138, DSISR: 20000000
TASK = c45de0f0[350] 'modprobe' THREAD: c4132000
Last syscall: 128
GPR00: 00000000 C4133E70 C45DE0F0 000000D0 C476AC90 00000021 00000000 
00000001
GPR08: C028F4ED 00000048 FFFFFFEB 00000061 33003553 1001E284 10017070 
00000001
GPR16: 00000000 00000000 00000000 00000000 00000000 100013A4 1001DF18 
1001E088
GPR24: 00000000 C476AE00 00000000 C4133EE8 00000021 00000220 C476AC90 
00000000
NIP [c62cc038] snd_pmac_dbdma_alloc+0x38/0x104 [snd_powermac]
LR [c6238bcc] snd_pmac_new+0x8c/0x484 [snd_powermac]
Call trace:
  [c6238bcc] snd_pmac_new+0x8c/0x484 [snd_powermac]
  [c6238048] snd_pmac_probe+0x48/0x320 [snd_powermac]
  [c6238330] alsa_card_pmac_init+0x10/0x2c [snd_powermac]
  [c003b4e4] sys_init_module+0x264/0x394
  [c0004060] ret_from_syscall+0x0/0x44

I can do a binary search of the versions between 2.6.8 and 2.6.12-rc3 to 
see when it broke if that will help.
Config and dmesg attached.