[cups.general] Writing Filters - Permission denied

[Lukas Thiemeier]

Hello there,

I've a problem running my own Cups-filters.

The Filter itself works just fine. I've changed the mime.convs to make
Cups use it, and the Printers output is great.
(mime.convs: text/plain application/vnd.cups-postscript 33 a2ps_wrapper)

But i do not want to use this filter for ever printer, but only for one
single queue.
So I changed back the mime.convs Entry to use texttops, and changed my 
queues ppd in /etc/cups/ppd:
new Entry in test.ppd:
 	*cupsFilter: "text/plain 33 a2ps_wrapper"

When I now print on this queue, Cups tries to start the correct Filter,
but is not able to. The error.log says:

I [23/Aug/2007:18:14:58 +0200] [Job 3331] Started filter /usr/lib/cups/filter/a2ps_wrapper (PID 16734)
D [23/Aug/2007:18:14:58 +0200] Discarding unused job-state event...
D [23/Aug/2007:18:14:58 +0200] cupsdProcessIPPRequest: 26 status_code=0 (successful-ok)
D [23/Aug/2007:18:14:58 +0200] [Job 3331] /usr/lib/cups/filter/a2ps_wrapper: Permission denied
E [23/Aug/2007:18:14:58 +0200] PID 16734 (/usr/lib/cups/filter/a2ps_wrapper) stopped with status 22!
D [23/Aug/2007:18:14:58 +0200] [Job 3331] File 0 is complete.
E [23/Aug/2007:18:14:58 +0200] [Job 3331] Job stopped due to filter errors.

The whole World may read and execute the Filter, and if i start it from 
the commandline as root or as user lp, its just fine.

Do I have to introduce the Filter to Cups in some way? Or Do you have any 
other ideas? For me, the most confusing part of this Problem is, that the 
Filter works perfectly if I put it in mime.convs, but Cups has no 
permissions to start it using the PPD-Entry.

Thanks for your Help, and excuse my bad English, please :)

greetings, Lukas Thiemeier