I'm facing a strange issue, I have vps-link3 account with hostinabox server, I enabled domainkey from the lxadmin area and run /script/fixdomainkey every thing worked well then and all my out going emails had domain-key header but few days later this signature disappeared!! any one faced the same problem? I tried to disable then enable and run /script/fixdomainkey but this didn't solve the problem, any thought?

Thank you