iceweasel beta on testing

[Kwadronaut]

Hi,

Following instructions on http://mozilla.debian.net/ seems that
beta is currently not installable on testing

The following packages have unmet dependencies:
 iceweasel : Depends: xulrunner-21.0 (>= 21.0~b1-1) but it is not going
to be installed
E: Unable to correct problems, you have held broken packages.

➜  ~  sudo apt-cache policy xulrunner-21.0          
xulrunner-21.0:
  Installed: (none)
  Candidate: 21.0~b1-1
  Version table:
     21.0~b1-1 0
        500 http://mozilla.debian.net/ experimental/iceweasel-beta amd64
Packages

The following packages have unmet dependencies:
 xulrunner-21.0 : Depends: libnspr4 (>= 2:4.9.6~) but 2:4.9.2-1 is to be
installed

And that doesn't seem to be available in mozilla.debian, however it is
in regular sid repositories:

➜  ~  apt-cache policy libnspr4                     
libnspr4:
  Installed: 2:4.9.2-1
  Candidate: 2:4.9.2-1
  Version table:
     2:4.9.6-1 0
          1 http://ftp.de.debian.org/debian/ sid/main amd64 Packages
 *** 2:4.9.2-1 0
        990 http://ftp.de.debian.org/debian/ wheezy/main amd64 Packages
        100 /var/lib/dpkg/status

I'd be interested in a 'best practices' to solve this issue.

Ciao,
kwadronaut