I did note in the comment about PHP support. I did notice the website mentioned C++/ObjC, but I just lumped those in as C variants. The Java integration looks interesting.

The author in a forum post did say that he doesn't think that FCGI is the right way to go and suggested asking Zend to build a C library for GWAN that could run PHP code [1]. I find that unlikely unless GWAN really starts getting a large following.

[1] http://forum.gwan.com/index.php?p=/discussion/comment/3801/#...