Can't put documents into fax queue

["Betterton David(AUS Melbourne)" <BettertonD@logica.com>]

When I attempt to put documents into the fax queue I get the error :
"
Your facsimile job to 92034410 was not sent because document conversion
to facsimile failed.  The output from the converter program was:

Could not reopen converted document to verify format
<docq/doc33.cover;30>

Check any PostScript documents for non-standard fonts and invalid
constructs.
"
I've added the filename to the output (using strcat with outFile) as I
couldn't work out what it was.

I've managed to get a couple of documents accepted, but only just after
the servers (hfaxd and faxq) are restarted.

A configuration problem ?

I have:
Hylafax  4.0p10
gcc 2.7.2
on
Dec Alpha OSF 4.0

Dave