Edgar,this has happened to me several times, usually when our mail server was down, but normally I've had notices from majordomo@virginia.edu that I was being dropped from the list as a warning in case it was an accident.
There's been some stuff of interest the last three or four days; I'd be happy to send you copies of the digests of what you've missed if you let me know what the lost post you received was.
Regards, c