cbbrowne at ca.afilias.info said:

> The problem is that Slony-I can't start until that old transaction that
> may predate the installation of Slony-I components completes.
>
> If you peek in at pg_locks and/or pg_stat_activity, you'll presumably see
> that some transaction is under way (namely #1177475, though that number
> may not be easy to see).
>
> Kill that connection and the floodgates will open :-).

Interesting, thank you!  That seemed to do the trick.  The only thing I
can think of that did that was when I was experimenting using psql nd was
sloppy about my begin and commit/rollback statements.

Don't pending transactions ever time out?