getnetbyaddr not working with LDAP

I'm running 2.3.39 under Redhat 4.0. I'm transitioning my Redhat clients from NIS to LDAP. It seems that getnetbyaddr doesn't work under LDAP. The following perl code shows the problem:

#!/usr/local/bin/perl -w use Socket; $n = getnetbyname ( "nasd" ); $name = getnetbyaddr($n, AF_INET); print "$name\n"; exit 0;

Host running NIS: # ./eric.pl nasd

Host running LDAP: # ./eric.pl Use of uninitialized value in concatenation (.) or string at ./eric.pl line 9.

The getnetbyname call works and I can print out the network IP. Can anyone help with this?

Thanks