pkgng repository URL for minor version

[Oleg Ginzburg]

What is the method in a repository of pkg there to split packages for 
difference minor  version? At present PACKAGESSITE set to 
http://pkg.freebsd.org/${ABI}/latest, where $ABI forming URL on 9.0 or 
9.1/amd64 into http://pkg.freebsd.org/freebsd:9:x86:64/latest/

How it is possible to specify necessary minor version or determine for which 
version the package. For an example, some software builds on 9.1 isn't 
compatible with 9.0 libraries ("_ThreadRuneLocale" Undefined symbol)