I would first contact the author of the module and see if you can work something out. Otherwise, fork. Beside that some of the other mentioned points don't work, you'd break all rules of software engineering. Your extension code is now dependent on the implementation details of the original code, and it's not using the API. If in a next version of YAPE::Regex, %pat is renamed, or worse, due to reimplementation of the internals, there's now a different datastructure, your extension code no longer works.

Abigail