memcached_clone() and distribution hash bug

[ping,cai]

when we new a memcached_st, and set hehavior of MEMCACHED_BEHAVIOR_KETAMA,

////code//////////////
memc = memcached_create(NULL);

memcached_behavior_set(memc, MEMCACHED_BEHAVIOR_KETAMA, 1);

clone = memcached_clone(NULL, memc);

printf("%llu\n", memcached_behavior_get(memc, MEMCACHED_BEHAVIOR_KETAMA_WEIGHTED));
printf("%llu\n", memcached_behavior_get(clone, MEMCACHED_BEHAVIOR_KETAMA_WEIGHTED));

//////////code//////////////

the value of MEMCACHED_BEHAVIOR_KETAMA_WEIGHTED is different, which will cause the miss match of key mapping.

the course of the problem is, in the function memcached_clone（）， the ketama value in "memc" is not copied to "clone"