Setting up apt when have mixture of testing, sid and experimental

[Csanyi Pal <csanyipal@gmail.com>]

Hi,

I'm running Debian GNU/Linux SID.

My sources.list is:
deb-src http://ftp.debian.org/debian/ sid main contrib non-free
deb http://ftp.debian.org/debian/ sid main contrib non-free

deb-src http://ftp.debian.org/debian/ testing main contrib non-free
deb http://ftp.debian.org/debian/ testing main contrib non-free

deb-src http://ftp.debian.org/debian/ experimental main contrib non-free
deb http://ftp.debian.org/debian/ experimental main contrib non-free

deb http://www.deb-multimedia.org sid main
# deb http://www.deb-multimedia.org testing main

# Bitlbee
deb http://code.bitlbee.org/debian/devel/testing/amd64/ ./

# GNUstep
deb http://coyote.octets.fr/pub/gnustep/packages/wheezy/amd64/ ./

Yesterday when I want to install the 'kazam' package, I get message in
the aptitude interface:

liborc-0.4-dev depends on liborc-0.4-0 (= 1:0.4.17-2)

and this is a broken package now.

I get an advice from the kazam's package maintainer Andrew
Starr-Bochicchio: 
<quote>
You seem to have a mix of packages from both unstable and testing
installed. liborc, which is an indirect dependency of kazam, currently
has different versions in unstable and testing. Starting from a fresh
unstable chroot, I can install kazam with no problems.
</quote>

Now, how can I set up my apt system to avoid such a conflict?

-- 
Regards from Pal