mysql> select memc_servers_behavior_set('MEMCACHED_BEHAVIOR_SUPPORT_CAS', '1');
+------------------------------------------------------------------+
| memc_servers_behavior_set('MEMCACHED_BEHAVIOR_SUPPORT_CAS', '1') |
+------------------------------------------------------------------+
|                                                                0 | 
+------------------------------------------------------------------+
1 row in set (0.01 sec)

mysql> select memc_set('key1', 'value1');
+----------------------------+
| memc_set('key1', 'value1') |
+----------------------------+
|                         31 | 
+----------------------------+
1 row in set (0.00 sec)

mysql> select memc_get('key1');
+------------------+
| memc_get('key1') |
+------------------+
| value1           | 
+------------------+
1 row in set (0.00 sec)

mysql> select memc_cas('key1', 'foarejajaj', 0);
+-----------------------------------+
| memc_cas('key1', 'foarejajaj', 0) |
+-----------------------------------+
|                                 8 | 
+-----------------------------------+
1 row in set (0.00 sec)

mysql> select memc_cas('key1', 'foarejajaj', 1);
+-----------------------------------+
| memc_cas('key1', 'foarejajaj', 1) |
+-----------------------------------+
|                                 0 | 
+-----------------------------------+
1 row in set (0.00 sec)

mysql> select memc_cas('key1', 'eeeeeeeeee', 1);
+-----------------------------------+
| memc_cas('key1', 'eeeeeeeeee', 1) |
+-----------------------------------+
|                                12 | 
+-----------------------------------+
1 row in set (0.00 sec)

mysql> 

<5 new client connection
<5 set key1 0 0 6
>5 STORED
<5 quit
<5 connection closed.
<5 new client connection
<5 get key1 
>5 sending key key1
>5 END
<5 quit
<5 connection closed.
<5 new client connection
<5 cas key1 0 0 10
>5 ERROR
<5 foarejajaj
>5 ERROR
<5 quit
<5 connection closed.
<5 new client connection
<5 cas key1 0 0 10 1
>5 STORED
<5 quit
<5 connection closed.
<5 new client connection
<5 cas key1 0 0 10 1
>5 EXISTS
<5 quit
<5 connection closed.