I am running a pg_receivexlog 9.2 client against a 9.1 server. It seems to work. Comments in the code seem to indicate that this setup is workable.
However, pg_receivexlog is not part of the 9.1 source tree nor the rpm package (as far as I see), so I am curious if there is some caveat that I sure be aware of, or some other incompatibility that makes this setup not work.
The goal is to have PITR using a combination of pg_basebackup (which is part of 9.1) and pg_receivexlog.