mysql apache charset problem

[foxphiles]

mysql apache charset problem

hi, i have this strange problem.
i use thai language and when i query data from mysql the character comes out right, sometimes. and sometimes just unreadable.

here is example of the output.
<< this comes out right

<< this is wrong

those two output is done at close time together, just refresh the browser and results change.
any idea where i should go check?

thanks in advance.