LISTSERV doesn't support addresses longer than 79 bytes for subscribing
to mailing lists. Note that this has nothing to do with punched cards,
it's just a field length in a RECFM F file and 80 looked like a good
choice since it is the number of columns on most terminals. There is
nothing you can do about it, other than suggest to our honourable UK
colleagues that explicit routes are bad enough without having to be used
multiple times on a single address.
Eric