asterisk users - Oct 2011 - Asterisk IAX Trunking Stops - Too much delay in IAX2 calltoken timestamp from address

Hi all,

Just hit this problem for the first time:
WARNING[17712] chan_iax2.c: Too much delay in IAX2 calltoken timestamp
from address 10.25x.xxx.160

When I ran "iax2 show peers" everything comes up as unreachable, no
calls are passed between the servers (as would be expected) but there
is no problem with DAHDI / SIP channels. At the same time there are no
network issues (can ping all the servers). The IP address that comes
up in the error message is an Elastix box which is connected via IAX
and happens to be the first peer listed in the output.

Running "iax2 reload" did nothing; the system just sat at the CLI
prompt. I eventually ran "service asterisk restart" and that fixed the
problem.

Two questions;
1. How do I avoid this error coming up again?
2. How do I stop this error (if it can't be fixed) from stopping all
the other peers from working?

Thanks for any pointers you can give me.