"Josh Harrison" <joshques@xxxxxxxxx> writes: >> What version of Slony? same for both servers? > Yes slony version 1.2.12 Judging from the error message, you can't do that --- you need at least different versions of the .so file for 7.4 and 8.1. (GetTopTransactionId did not exist in 7.4.) But this is the wrong place to be asking about that; the slony lists would have people who know more. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org/