Q: device not configured

[V+]

Hi all,
I'm trying to use gnupg for providing a print spooler (LPRng) with
authentication services for users. For simplicity I invoke the gpg program
from a filter in the server side. When I submit a printjob from a client
machine to the print server, the printjob is processed by the filter and the
result is sent to the printer. This is the standard behavior for filters. My
problem is that when I sent a printjob from a remote client to the server the
authentication process fails and the next error is logged in the server log
file:

     gpg: cannot open /dev/tty: Device not configured

Does anybody know what does it mean? I've used the gpg debug options but I
don't understand the output information. If some of you get this error even
in a completely different context (not using LPRng) your suggestions can help.
Thanks in advance.

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_/ Vicente Mas                   _/                       _/
_/ Dpto. Técnico, Servicom 2000  _/                       _/
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