I focused same topic that you are said about.

I am using spymemcached client to write the cache and nginx read wrong data.

After your reply i tried to write with whalin memcached client and tried to read both spymemcached and nginx. Neither nginx nor spymemcached can read data from cache.

Does nginx have any configuration that i configure which memcached client nginx use? Or anyone know which memcached client can run with nginx properly?

Emre