Having just suffered this when we upgraded one firewall to 
2.6.18-274.7.1.el5 I did some searching in TUV's bugzilla and found a 
report which seems strikingly similar - the kernel panics when iptables -j 
REJECT sends an icmp back over a bridged interface...

   https://bugzilla.redhat.com/show_bug.cgi?id=749813

From that report it seems to affect all the 2.6.18-274* series of kernels 
so we have backed off to 2.6.18-238.19.1.el5 for now - which appears to be 
stable.

I'm posting this here not because I expect any of the SL people to fix it 
(I don't expect there to be a fix until TUV releases one), but in case 
anyone else is suffering the same crashes and hasn't yet found the 
combination of things which trigger it.

-- 
/--------------------------------------------------------------------\
| "Computers are different from telephones.  Computers do not ring." |
|       -- A. Tanenbaum, "Computer Networks", p. 32                  |
---------------------------------------------------------------------|
| Jon Peatfield, _Computer_ Officer, DAMTP,  University of Cambridge |
| Mail:  [log in to unmask]     Web:  http://www.damtp.cam.ac.uk/ |
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