After more playing with Tailor, I managed to hack it enough to convert my Arch repositories to Subversion. Move from distributed to non distributed VCS migth look as step backwards, but I have pretty good reasons for this:

• Subversion is widely used and there is big chance that potential contributor will know how to use it. This lowers barrier for contributing (especially when compared to current Arch/Bazaar).
• Subversion sucks much less than CVS which is other well known VCS.
• If I want to work distributed I can still use Bazaar-NG with foreign branch features.

The conversion is currently on the way and will probably need some time (about half of Gammu revisions have been converted so far).