Strange error (Socket command option unknown)

Hello,

I hope this is the right list to post this question.

I'm at a loss trying to figure out a strange error message
I'm getting (at an excessively high rate -- around 200 times
per day, out of a total of several hundred thousands statements
executed per day).

The error message reads:

"FATAL 1: Socket command option e unknown"

And the server closes the connection. Actually, the
complete error message contains several lines, and reads:

FATAL 1: Socket command option e unknown
server closed the connection unexpectedly
This probably means that the server terminated abnormally
before or while processing the request.

Except that the server does not shutdown (more statements
continue to arrive, and they're executed).

I checked the docs, but I can't figure out what may be
happening, so I'm at a loss at trying to determine what to
do. (the one thing I did notice is that it is related to
one specific statement -- however, it's not that the
statement is unconditionally wrong: it does execute
several thousand times per day, and it succeeds most of
the time)

Any ideas? Pointers where to look for more information
would also be highly appreciated!

Thanks,

Carlos
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