Etags in the current Emacs distribution (23.3) does not support the OOP syntax of PHP5. I found a patch at
http://old.nabble.com/-Patch--etags-support-for-php5-td12843865.html and applied it to etags.c found in the lib-src of the emacs source code. This patch applies, compiles and works as-is on my Mac OS X 10.6.7 machine. It produces a very nice TAGS file for my PHP projects. I think this patch would make Emacs much more attractive to PHP coders. My question is, why was this patch not incorporated into the main emacs distribution? I will gladly offer any help or support to make this happen!