We are considering running our own mail server but our ISP only provides dynamic IP addresses.
Haven't used TZO, but I've been using dyndns.org for about a year and a half without a single problem. Their basic service is free, but only provides you with <something>.homeip.net or something similar, but you can just point your mail.company.com subdomain at <something>.homeip.net, and you'll be set.
I ran into this service last week:
I second dyndns... and they appear very financially viable from what I've seen.
dir at badblue com
Thanks for you help :-)
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