For the Debian packages, I have a simple test script, which you can see here:

http://anonscm.debian.org/viewvc/pkg-postgresql/tags/slony1-2/2.0.7-4/debian/slony1-test.sh?view=markup

It creates a master and a slave instance, replicates a few rows, and see if they arrive.  This script has worked essentially unchanged since the 1.2 days.

Now I upgraded the package from 2.0.7 to 2.1.2, and when I run the test script, the call

store listen ( origin = 1, provider = 1, receiver = 2 );

(line 82 in the above link) hangs and keeps writing messages like this indefinitely:

<stdin>:14: waiting for event (1,5000000007) to be confirmed on node 2

I have removed the store listen calls, since they are obsolete, but it's still suspicious that this doesn't work anymore, especially since there are changes in slony 2.1 regarding implicit waiting.  So maybe this should be investigated.