sporadoc 6204 errors during compile

I get a 6204 occasionally error while compiling.

It looks like others have had the same problem (see
http://www1.4js.com/html/mlarchive/msg07248.html )

It's not happening quite as frequently to me, but it is happening enough to
prevent us from being able to cleanly compile all our code all the way
through without manual intervention.

It isn't consistent - when I get the error, I can run the fgl2p command and
it works fine.  Similarly if I restart the compile process, it will not fail
in the same place.


We're running commands like this:
fgl2p -o IMSmschd00.42r IMSmschd00.42m IMSmschd01.42m IMSmschdE1.42m
IMSmschdU1.42m /dsc_trn/d4gl/lib/lib*.42x

And when it fails, the error looks like this:
ERROR(-6204):Module 'SFFrmenuUj': Unknown opcode.