Changing Cyrus to accept 8bit subjects

[Rayed Alrashed]

Hello all,

I just modified my Cyrus IMAP to make it accept 8 bit subjects without 
changing it to the letter 'X', I changed these two files:
imap/lmtpengine.c
imap/message.c
I tested it and it seems to work fine.

My question is this change safe? I am afraid it might break Cyrus 
database format.

Thanks
Rayed