porting a php3 module/patch to php4

Having seen Richard Lynch write recently on this list: : There really were very, very, very few changes from PHP3 to PHP4, : considering it was a complete re-write of the engine. I think I am going to break down and ask for tips, tricks, etc, porting a php3 module to php4. This thing was written by someone else to be part of php-3.0.6 (!) and adds a few functions for accessing a specialized database to PHP. It was intended to live in the dl/ directory. What is it going to take to get this to work in ext/ or where- ever it should be for php4? Benjamin