As reported on the mailing list thread http://lists.slony.info/pipermail/slony1-general/2014-May/012811.html
Slonik can hang during a failover because a non failover candidate node can be using a second failed node as its subscription provider. It should be reconfigured to use one of the remaining nodes as the subscription source but this isn't happening.
Created attachment 202 [details]
(In reply to comment #1)
> Created an attachment (id=202) [details]
> proposed patch
Tested here and behaves as expected. Thanks again Steve.
This was committed