Comment 2 for bug 36055

This patch will fix it:
--- php-mode.emacsen-install.orig 2007-02-08 01:07:16.000000000 -0600
+++ php-mode.emacsen-install 2007-02-08 00:57:19.000000000 -0600
@@ -16,7 +16,7 @@
 if [ ${FLAVORTEST} = xemacs ] ; then
     SITEFLAG="-no-site-file"
 else
- SITEFLAG="--no-site-file"
+ SITEFLAG=""
 fi
 FLAGS="${SITEFLAG} -q -batch -l path.el -f batch-byte-compile"

Here are detailed instructions on how I modified the source and compiled the binaries:
http://speeves.erikin.com/2007/02/ubuntu-php-mode-fails-to-install.html