$haystack = "AbCDEf";
$needle = "CD";
stristr ( $haystack,$needle);
echo $haystack;	// prints 'abcdef'
echo $needle;	// prints 'cd'

My configure line,
./configure --prefix=/usr \
--with-apxs=/usr/sbin/apxs \
--with-config-file-path=/etc/httpd \
--disable-debug \
--enable-debugger \
--enable-magic-quotes \
--enable-track-vars \
--with-system-regex \
--with-xml --with-zlib \

php.ini (no change, use default)