After many try,i found the problem,it is only works for the user created at xeams,and pop from xeams.
For example,i have use admin@xxx at xeams,and i pop download email from xeams,the tagging body work.
If i use Hybird mode,mail deliver to next downstream,none users are apply the tagging body. I think as long as recipients domain is at xeams,tagging body need to work.
Pls check the issue