Confused with Backports.org

[phafit]

Hi,

i'm a bit confused to update my working cyrus 2.2 installation.

i have a amd 64 sarge.

so now my problem i previously used

deb http://mail.incase.de/cyrus22/ sarge main

to get latest updates. and it works great.

so after looking for a 8 bit patch for cyrus i read the message that 
mail.incase.de not longer maintained and i should use backports.org.

ok great so backports uses version 2.2.13-3bpo1 of all cyrus releated files.
but i have 2.2.12-4bpo1 installed.

after updating only the cyrus-docs-2.2 has been updatet to the new version.

so i think the problem is that @ backports no 64 bit binarys available.

so what should i do? install from source? where could i get a 
2.2.12-4bpo1 + version for amd 64?

thanks

phil