How to install different versions of memcache with different versions of lampp

The simples solution. You need memcache.so build with API 20060613. This is pretty old, but if you go to http://packages.ubuntu.com/hardy/php5-memcache you will find both amd64 and i386 packages. Run

uname -m

to see what architecture you have and download the package accordingly. After you downloaded the package just go in mc open the package, get the memcache.so and copy it on /opt/lampp/lib/php/extensions/no-debug-non-zts-20060613/, and add in php.ini

extension=memcache.so

if is saying it doesn't find memcache.so probably you should adjust extensiondir accordingly.

Restart apache and look at php_info(); It should be there.

On future try to stick on ubuntu/debian versions of php/apache/mysql and don't use lampp. I know is much more easy with lampp, but after you understand what it happen "under the hood" will be more easy for you to build your applications and to understand linux. Another problem with lampp are the security updates. If you are using Ubuntu or Debian versions you will have all the upgrades with the OS and the entire process of upgrading it will take seconds not hours or days.