I tried to install drools-compiler 5.3.1.Final in a OSGI container and got exception - 
Error executing command: Unresolved constraint in bundle org.drools.compiler [171]: Unable to resolve 171.0: missing requirement [171.0] module; (&(bundle-symbolic-name=org.drools.core)(bundle-version>=5.3.1.SNAPSHOT)).

I guess it should depend on 5.3.1.Final, not SNAPSHOT

Alex