We had a problem with 1.2b10 with captive portal with no SSL. After approx 4
days of operation it stopped letting people through. No obvious errors, but
no captive portal page and all traffic was blocked (apart from MAC and IPs
specifically allowed). Turning the captive portal off got traffic flowing
again without a reboot.
 The only log entries around that period are (it failed sometime the evning
of:Oct 4):

Oct 7 01:36:02 last message repeated 12 times
Oct 7 01:35:29 /kernel: arplookup 0.0.0.0 <http://0.0.0.0> failed: host is
not on local network
Oct 7 00:54:07 last message repeated 21 times
Oct 7 00:51:42 last message repeated 57 times
Oct 7 00:41:38 /kernel: arplookup 0.0.0.0 <http://0.0.0.0> failed: host is
not on local network
Oct 5 09:48:03 last message repeated 5 times
Oct 5 09:47:55 /kernel: arplookup 0.0.0.0 <http://0.0.0.0> failed: host is
not on local network
Oct 4 22:04:28 msntp: resetting on error 0.233 > 0.205
Oct 4 22:04:28 msntp: resetting on error 0.233 > 0.205
Oct 3 20:58:24 /kernel: arplookup 0.0.0.0 <http://0.0.0.0> failed: host is
not on local network
Oct 3 20:19:26 /kernel: arplookup 0.0.0.0 <http://0.0.0.0> failed: host is
not on local network

We don't have a convenient way of monitoring captive portal failure so we've
left it off, but just in case someone else is having the same problem... The
portal was created from scratch with 1.2b10 and uses the built-in login
database with one user, guest, built into the signin page (that way we get a
log entry). This was a Soekris 4801 (128MB RAM).
I'll probably get brave, and try 1.2 and see what happens...
 cheers, michael