Error I don't understand, losing synch with server

Every once in a while I log this error executing a query:

message contents do not agree with length in message type "D"
lost synchronization with server: got message type "O", length 1398030676

And from that point forward any use of the connection just returns a null
result.

I'm running 8.0.4 on OS X 10.4.4 Server. Does this look more like a possible
bug in PG, or me corrupting memory? For what it's worth, this is currently
the only real problem I'm having, no crashes or other weirdness that would
lead me to suspect memory corruption in my own code.

It's also rare enough that I can work around it by noticing the error,
dropping the connection from my pool, and replacing it with a new one. But
ugh, that's not exactly a long-term solution.

Also FWIW, the only reason I haven't moved to 8.1 is lack of time. (My
available time last month got chewed up by a server hardware failure.)

--
Scott Ribe
scott_ribe(at)killerbytes(dot)com
http://www.killerbytes.com/
(303) 722-0567 voice