Chinese characters not properly saved

Hi All:

I have been struggling with a charset set conversion between client and
server, for the past few days.The output from the following query:

select subject_entity from t_crwl_entry where id=148252

is:  http://twd

which is correct. Now after I run an update query like this:
update t_crwl_entry set subject_entity='' where id=148252

and then re-run select query I get this characters
????????????

If anyone, could please shed some light on this issue or
a suggest a workaround i would appreciate it.


Thanks,

Yoanis.

P.D: I am not sure if those characters are Chinese, so I apologize for any
possible mistake.