PHP Extensions: C or C++?

I have a few PHP extensions that I'd be willing to share but I've never done this sort of thing before. I wrote a few extensions for work, and my company sees no problem in donating them to the open source world and to the PHP project, but I'm curious about something: Are extensions for PHP required to be coded in C, or will C++ do? I'm a C++ guy myself, and since PHP is largely written in C, does this cause a huge problem? If there's enough interest in any of my extensions, I'd consider a re-write from C++ to C, but I don't want to do that if I don't have to. The only extension really ready for prime-time right now is a rather simple Porter stemmer, written in ANSI/ISO C++ using things like the standard C++ string library and such. It's a simple extension that we're using to make the search engine we're building a bit easier to manage. Any future extensions are going to be focused on making search engines easier to implement in PHP. (We're building a search engine that uses PHP.) Any interest in that sort of thing? And if so, C or C++? J