If you have access to your nameserver you can edit the A record pop3.domain.tld and set a ttl of 60 seconds. If Masterpop faied just edit this entry and the lookup of pop3.domain.tld goes to your backup server.So I suppose that SMTP failover is more or less possible, now I'm stuck on the pop3 failover!Thanks again, David.
this is just an untested idea :-) rene