Use an accelerator and a caching engine?

I'm currently looking through the information on caching the system and I'm finding a lot of mixed information.  For example, one article says "It is fine to use eAcclerator, APC or XCache as PHP accelerator and Memcached as cache engine."

Looking through the advanced settings, I can only select a cache engine or eaccelerator.  So, how do I use both eAccelerator and a cache engine?

Yes you can select different caches engines for some of site's part. For example - you can use memcache for stored profiles info but use XCache for template only.