backend closing unexpectedly

Folks,

I have a moderately complex query running on small views (10-30
records) which used to work, but is now dying unexptecedly. The query
is via aolserver, but also creates the same response when using pgsql.

Within pgsql, I get:

pqReadData() -- backend closed the channel unexpectedly.
This probably means the backend terminated abnormally
before or while processing the request.
The connection to the server was lost. Attempting reset: Failed.

Within aolserver, I get:

Error: dbinit: error(localhost::acs,pqReadData() -- backend closed the channel unexpectedly.
This probably means the backend terminated abnormally
before or while processing the request.

I'm running postgresql-7.1.2-5PGDG, on RedHat 7.1...thoughts?

Thanks,

Adam