This worked for me, or a least it ran through the whole thing without any complaints. (When I run look at phpinfo.php it doesn't seem as though its been updated though... still shows version 4.2.1 and the original build date, can anyone explain that?)
Run the patch in the on the same level as the php src directory:
#patch -p0 < php-4.2.1-to-4.2.2.patch
patching file php-4.2.1/NEWS'
patching filephp-4.2.1/configure'
patching file php-4.2.1/configure.in'
patching filephp-4.2.1/main/php_config.h.in'
patching file php-4.2.1/main/php_version.h'
patching filephp-4.2.1/main/rfc1867.c'
#cd php-4.2.1
#./configure --with-apxs=/usr/sbin/apxs --with-mysql=/usr/local/mysql --enable-track-vars --enable-trans-sid --enable-ftp
#make
#make install
#/etc/rc.d/init.d/httpd restart