[Mailman-Developers] in-reply-to problem

hello all,

I am new to python and mailman. i have a problem, need to find a solution asap.

when getting mails to the mailman from Lotus Domino client 5.0.10, the mail's does not have In-Reply-To header. Because of this the mail does not get threaded properly. pls tell me how i can solve this isue.

Thanks Karthikeyan.S