Emulating Java Exceptions

Hi All, I'm porting Java Code to PHP, my question is: What is the best approach to emulate Java exceptions in PHP4? (I know ZE2 adds exceptions but I can't wait). When a Java method "throws" an exception it is difficult to handle as a "return" of an exception object since then I'd have to check in every sinlge line that calls a method if the returned value is an exception and then return and exception etc etc. (Chaning that up to the user would be a nightmare). So I need some clever ideas ;-) Thanks, Garland.