I do realize that and I did answer your question - I listed all supported now memory caches by vBET and you can clearly find there Memcache. So why are you convinced that I didn't answer your question - what do you need more?

If you need hint how to support Memcached here it goes:
1. Add in product file additional option for memory cache parameter
2. Import product file
3. Edit file includes/vbenterprisetranslator_class_cache.php
a) Copy class for Memcache
b) Change name in copied class to recognize as Memcached
c) Update body to support Memcached API (our classes are simple adapters this is why you will not have to do any changes in other places)
d) Add new case for your new option value in switch block on the top of the file, to create Memcached adapter object
If you want more specific hints - just please create feature request and Kamil will give you exact hints how to do it with code listings.