[Plugin: WP Super Cache] Memcached support in WP Super cache?

Yes. Make sure the WordPress object cache for the storage medium of your choice is installed and a checkbox will appear on the admin page. I blogged about it and it’s in 0.9.9.

Donncha

Oddly enough it is a lot slower with the memcached object cache in place ?? In general enabling the object cache takes trans/sec from 1000 to 100 ??

I presume your site was serving pages from static html files before? In a stress test that would be much faster.