[Evolution] How can change mail title encoding?

[Hongzheng Wang <wanghz02 mails tsinghua edu cn>]

Hello, everyone

I'm using Evolution 1.4.6 under Debian Sid. I found the composer's
character set can be set to any encoding. But that setting does not
affect the mail title's encoding. It seems evolution insist on using
UTF-8 encoding.
I wonder how can I change the default encoding of mail title from UTF-8
to others.

Thank you.

-- 
Hongzheng Wang
Department of Electronic Engineering
Tsinghua University
Beijing 100084, China
Tel: (+86 10) 6278 2690