I'm using V2.2d build 152 at the moment.
I've set use-ISO-date to yes, but it seems HFS sometimes forgets this setting. Which can result in log entries like this:
2008-03-09 08:22:40 207.210.215.90:59076 Disconnected by server - 6 bytes sent
09.03.2008 16:34:51 Server stop
2008-03-09 16:34:56 Server start
09.03.2008 16:38:02 DNS update requested for .......
Secondly, in the INI file, I noticed an entry called "dyamic-dns-host=" (sic, not "dynamic"). Obvious typo - I don't know what it does, or what it doesn't do if the typo is breaking it.
If I may digress for a moment...
How I noticed the typo mentioned above - I'm using DynDNS.com for a DDNS hostname, and HFS happened to fail to update my fresh IP with them (return code was "dnserr"). HFS then told me "user interaction is required", which is nice, but I wish it would have flashed in bright red at me that my DDNS still needs to be updated manually by me.
On that note, it might be useful to have a host check in HFS. I can self-test the server, I can check for my external IP - but there seems to be no provision for performing an actual lookup of the DDNS name to see if the found external IP really matches the IP that the DDNS name currently resolves to (and, if it doesn't match, warn me about it).