My guess is that this is what happened. 'exit' was invoked in the xterm
logged in as a-onl@adaql2 but datamon was running in the background. The
a-onl shell quit but the underlying ssh session didn't quit since it was
still running the X11 port-forward for datamon. People then got bored
and closed datamon which dumped its spew to stderr on exit and allowing
ssh to quit (giving the adaq@adaql2 shell control of the xterm stdin/out
again).