Hi Kat,
No. Go into wp-content/ and rename object-cache.php to object-cache.php.bak
This is the quick fix. I’m still looking for the correct solution.. but this will get you back into your admin.
Update
I’ve fixed it by renaming object-cache.php to object-cache.php.bak
This has been a work around to get back into the admin, but does anyone know what this has to do with the memecache plugin? I’d like to fix this problem if anyone knows a proper solution?