why is the package being pulled from testing?

[martin f krafft <madduck@debian.org>]

i have stable and testing sources in my sources.list, as well as the
following entries in /etc/apt/preferences:

  Package: *
  Pin: release a=stable
  Pin-Priority: 999

  Package: *
  Pin: release a=testing
  Pin-Priority: 333

now i am trying to install, say, mhonarc, which is being pulled from
testing:

  Get:2 http://sunsite.cnlab-switch.ch testing/main mhonarc 2.5.12-1

but apt-cache policy says that it should (correctly) come from stable:

mhonarc:
  Installed: (none)
  Candidate: 2.5.2-1.2
  Version Table:
     2.5.12-1 0
        333 http://sunsite.cnlab-switch.ch testing/main Packages
        333 http://ftp.de.debian.org testing/main Packages
     2.5.2-1.2 0
        999 http://security.debian.org stable/updates/main Packages
     2.5.2-1 0
        999 http://sunsite.cnlab-switch.ch stable/main Packages
        999 http://ftp.de.debian.org stable/main Packages

what am i doing wrong?

-- 
 .''`.     martin f. krafft <madduck@debian.org>
: :'  :    proud Debian developer, admin, and user
`. `'`
  `-  Debian - when you have better things to do than fixing a system
 
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