Postgres 8.4
Slony 1.2.20

I have a table that is not replicated. This table has a foreign key constraint to a table that is replicated. It appears that Slony modified the constraint so that it is not possible to drop the constraint. I get an error that says "error xyz is an index" where xyz is the name of the primary key on the table that is replicated. 

My questions are :

* how would one go about dropping a foreign key constraint for this non-replicated table if Slony has modified it
* where can I see the modifications to the Postgres catalog (some hints on where to look)
* what would happen if I added the table that is not replicated to the replication set? Would Slony add it without problems? I ask because I was a bit surprised that the non-replicated table was modified in this way and wonder if adding the table to replication would just compound problems. 

Thanks. 
Frank