At the moment, I don’t think any of my PHP software will run on PHP 5. This isn’t that big a deal as most ISPs don’t even offer PHP 5 as an option (and won’t for a little while), but it is something I plan to work on. I’d read so much about the backward compatibility of PHP 5 with PHP 4 scripts, I foolishly expected it to work.
One thing that I discovered in my brief testing: from within a class, you can no longer replace an object entirely. I have code in a class like this:
$this = foo($this);
that now throws a fatal error. I used this syntax with functions that would translate the encoding of a task, user, group, etc. and I’ll have to rewrite those. When I commented those lines out, things failed in a different way, so I’ll need to spend some time with it.