Weird DNS proxy issue on ECI Bfocus modem?

[Ori Berger]

The DNS proxy on my ECI ADSL modem ran flawlessly for years, but 
recently, every few days it will abort with a segmentation fault. (I've 
been away for a few months, so I don't know exactly when it started -- 
later than October, earlier than February).

Restarting it (by running "/sbin/dproxy -c /etc/dproxy.conf"), solves 
the problem, and there are no other visible problems.

A hardware failure is possible but unlikely, given that it's all solid 
state (flash + ram) that has been doing the same thing for years.

Another thing I suspect is bad, possibly malicious, DNS packets that 
make the proxy die. It's an old 2.4.17 MontaVista kernel, but I don't 
even know what version of dproxy.

I found <http://www.securityfocus.com/bid/23243/exploit> but the dproxy 
is not listening for requests from the world, and thus (assuming my own 
machine is not a zombie -- I'm optimistic!) if it is indeed relevant, 
then it's possible some upstream DNS servers are not playing nice.

Does anyone have a suggestion what I should be looking for, or to which 
firmware version should I update my modem?

Thanks,
Ori.