Mail Message format problem

Hi,

Please anyone help me in giving some insight upon how the character set conversion takes place when a mail is send from Notes to an internet user with attachments and multiple character set?

I require this information becose of a problem that I am facing. As a case, let me explain in some details.

When a client is replying to a mail, which was send in Chinese character set, in Japanese the recipiant (Outlook user) does not able to see both the char set and this appear in unreadable format. Now when he changes the char encoding he is able to view one set of characters and not both.

With Thanks and Regards.