it may all be academic anyway - no response! If they do respond and the price is right i would buy it anyway. Not just because of the DMOZ listing seeing as many believe that this would be deleted but for the many other long established links that the site may have, not to mention the traffic. If you can afford it i see buying old sites where the site owner has lost interest as part of a linking strategy along with the normal articles, directories etc....
sji2671 has a very sensible suggestion and is what I do on a regular basis. Redirecting a site says that the site doesn't have value anymore. It's a cue for DMOZ to delete their listing and, by association, for the Google Directory and others to follow suit. It's also telling Google that the site has no more useful content. That's a BIG message. You're not saying that a page has moved but you're saying that the whole site's reputation should be scrapped. Don't be surprised if Google removes the PR and rep it associates with that site. I'd buy it, revamp it, add a page or two of content, put a few carefully planted links on it to your new site..... and just keep renewing the domain and hosting every year.