Numbered stored procedures: introduction and deprecation?

SQL Server and Sybase ASE both support the highly dubious feature of grouping stored procedures by appending a number:

CREATE PROCEDURE Foo;1 AS ...
CREATE PROCEDURE Foo;2 AS ...

The only tangible benefit is that DROP PROCEDURE Foo will drop all of these procedures together — and that’s it; to call them you still need to append the number explicitly. The drawbacks of allowing a semicolon to be part of a procedure name and having non-obvious DROP semantics should be obvious, and indeed many tools don’t (properly) support this format and things like contained databases outright forbid them.

In what version of SQL Server and/or Sybase ASE was this feature introduced, and from what version onwards was it deprecated? I’d consult the documentation, but documentation that goes back far enough does not appear to be available. I’ve found the following:

• SQL Server Books Online 2005 already mentions them as deprecated.
• SyBooks Online for ASE 12.5 mentions it as being available there as well, but having a flag to disallow them.

This leads me to think the feature might have existed in very early versions indeed, possibly before the split between Sybase and Microsoft, but still doesn’t tell me what the earliest introduction and deprecation was. The asteroid to kill this dinosaur is still in orbit, but how old is the dinosaur?