Nsca 2.6 allowed_hosts in config file

hello -

in setting up a new monitoring server, i simply copied the configurations from the previous server for nagios and nsca (i’m running nagios 2.6 and nsca 2.6 on a debian etch box) - the problem being that the passive checks on client servers are no longer working, and the only difference there seems to be is that nsca, which was the same version on the previous server, will not start as a daemon if there is an allowed_hosts line in nsca.cfg on the host server, whereas it did work previously. does anyone have any thoughts?