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