Is there a good php syntax highlighter for Emacs? I'm using Emacs 23. I've tried php-mode, but that doesn't do anything. I've tried nXhtml, but that ignores my color theme and reverts to some awful looking default. Is there one I've missed or perhaps a configuration setting I've ignored?
I used this one http://www.emacswiki.org/emacs/php-mode-improved.el for some times. But I switched back to nxhtml as I have to edit too many badly mixed php/html/js/css files these days.
I tried the deboutv one but it sux on emacs (it was created for xemacs) and the development has been dead for some time with some bad bugs left.
You should try the modes available on emacswiki and see if one is good enough for you. If not, well, you know what to do : create your own.
The php-mode you linked to most definitely provides syntax highlighting. If it "doesn't do anything", then you didn't install it correctly. You might want to re-check your configuration.
I think that nXhtml does not do anything with your color theme. It is rather your color theme that does not know about the background colors that nXhtml put on chunks with different major modes.
The different background colors are there so that you will be aware that you have the full capabilities of Emacs html editing in the html parts and the capabilities of the php editing mode you are using in the php parts.
You can just tell nXhtml to not color the background if you prefer that.