how to report bugs from backports?

[Alain Baeckeroot <alain.baeckeroot@laposte.net>]

hi
i have filled a bugreport for OOo bpo50-2 in the debian bts, and was told
it is not the place to do it !
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=537315

i looked in backports.org and saw nothing wrt bugreport, so now i'm 
a bit confused :)

what should i do ?
Why backports bugs are not in the same bts as testing/unstable ... ?
(I think backport is a good testbed for new apps, as it allow to 
separate bugs caused by apps or by environment.)

Thanks
Alain.