I'm not sure if the original poster is still monitoring this, but I'll ask the question anyways.
The original post requested to be able to:
To automatically "lock" the current
procedure you are working with, so
nobody else in the team can make
changes to it until you are finished.
Perhaps the problem here is one of development paradigm more than the inability of a product to "lock" the stored proc. Whenever I hear "I want to lock this so noone else changes it" I immediately get the feeling that people are sharing a schema and everyone is developing in the same space.
If this is the case, why not simply let everyone have their own schema with a copy of the data model? I mean seriously folks, it doesn't "cost" anything to create another schema. That way, each developer can make changes until they're blue in the face without affecting anyone else.
Another trick I've used in the past (on small teams) when it wasn't feasible to let every developer have their own copy of the data because of size, was to have a master schema with all the tables and code in it, with public synonyms pointing to it all. Then, if the developer wants to work on a stored proc, he simply creates it in his schema. That way Oracle name resolution finds that one first instead of the copy in the master schema, allowing them to test their code without affecting anyone else. This does have it's drawbacks, but this was a very specific case where we could live with them. I would NEVER implement something like this in production obviously.
As for the second requirement:
To automatically send the changes you
make in the stored procedure, in an
Oracle database, to a Subversion, CVS,
I'd be surprised to find tools out there smart enough to do this (perhaps an opportunity :). It would have to connect to your db, query the data dictionary (USER_SOURCE) and pull out the associated text. A tall order for source control systems where are almost universally file based.