Just thought I'll share a “fun" story. Friend reported weird bug – OmniPITR reported that xlogs are sent to archive, but they actually weren't.
After some checking we found out that he was giving custom rsync-path (–rsync-path – path to rsync program) – and the path was broken.
In this case – OmniPITR was not reporting error, and quite happily was working under assumption that it works OK.