Hi all;

we're using slony to upgrade from 8.3 to 8.4
we're running slony V 1.2.20

When we try to initialize the slony cluster we get this:
<stdin>:351: PGRES_FATAL_ERROR load '$libdir/xxid';  - ERROR:  could not load 
library "/usr/lib64/pgsql/xxid.so": /usr/lib64/pgsql/xxid.so: undefined symbol: 
SerializableSnapshot
<stdin>:351: Error: the extension for the xxid data type cannot be loaded in 
database 'dbname=vmcorp host=10.1.3.95 port=5432 user=slony1'

Is this a version issue?  Is version 1.2.20 compatible with both postgres 
version (8.3 and 8.4)? If not, which version is?

Thanks in advance...