John Sidney-Woollett wrote:

> It doesn't make sense to me either. The error was always for the same 
> OID.
>
> Like you I assumed that removing slony would not cause any problems to 
> a running app.
>
> Hopefully someone more involved in Slony will be able to explain why 
> my pl/pgsql functions all got broken after uninstalling slony, even if 
> the issue is an artifact of postgres rather than slony itself.
>
> At any rate, I think that a warning is definitely needed in the slony 
> manuals for the slonik uninstall node command.

The nature of the problem has been fairly nicely documented, so I have 
added a FAQ entry on this as well as warnings in the manuals for both 
DROP NODE and UNINSTALL NODE.