Content-Length: and Lines: headers

[Jon]

Hi,

I've noticed that whenever Mutt writes out a message (e.g. when saving a 
message to another directory) it adds a Content-Length: header to the 
output, and sometimes a Lines: header as well.

Can I turn this behaviour off? AFAICT these headers are just some hacks 
for mbox files, but I only use Maildirs.

I'm using Mutt from Debian testing.

Thanks.