xpdf can not print via cups if started from firefox

[O. Hartmann]

Hello.

I've got a weird problem here. Very often I download scientific papers 
as pdf from protals and they got opened via firefox3 with the configured 
propper utility, in this case xpdf. In such a case, printing is 
impossible. I hit the print button, a popup shows up with the configured 
CUPS printing queue, but hitting OK doesn't have any effect. The funny 
thing is: when opening the same PDF (it is stored in /tmp/) with xpdf by 
starting xpdf from a terminal, printing on the same queue works well.
I realized that the change of this behaviour occured a long time ago 
when the cups printing system got an update. I never figured out what's 
the diffrence between starting xpdf via terminal and starting via 
firefox. My first guess was that my local ~/.xpdfrc does have effect, as 
the right configured CUPS printing queue showed up, but even the 
firefox-started xpdf client shows the right printing queue, so this 
implies that xpdf also reads my ~/.xpdfrc.
I'm not sure what's going wrong. I have no clue what kind of paper 
information is passed to xpdf by being called via firefox. Any help 
appreciated.

Thanks,

Oliver