Problems with TFTP.

I have Zen on a Server at a remote site dhcp and pdhcp on same server option
60 set all has been working find no config changes on the server or any new
sp's anyway to day tried to blast a box was having none of it so ran zfdstop
and the zfdstart logger is saying using sys:\tftp from sys:\system\tftp.ini
as tftp data directory using ip address (xx.xx.xx.xx) specfied in ini file
failed to bind to xx.xx.xx.xx

Any ideas?