I need to join my SLED machines to a Win2008 domain and get an FQDN that has forward and reverse DNS accessible from other machines on the network. I've changed the domain names for this post but everything else is straight from my configuration.

dc1.domain.local ( is the primary dns. It provides DHCP as well as authentication on domain.local
dc2.my.domain.local ( is the secondary dns and provides authentication on the my.domain.local subdomain

test.my.domain.local ( is my SLED11 SP1 machine. It gets its IP via DHCP from dc1 without any problems. It gets its system time from dc2 via NTP. It appears on both nameservers under forward and reverse DNS, but when I try to join the domain I get the following:

test:/ # net ads join -U testadmin
[2012/03/08 12:54:27, 0] param/loadparm.c:7457(lp_do_parameter)
Ignoring unknown parameter "winbind seperator"
Enter testadmin's password:
Using short domain name -- MY
Joined 'TEST' to realm 'my.domain.local'
[2012/03/08 12:54:33, 0] utils/net_ads.c:1080(net_update_dns_internal)
net_update_dns_internal: Failed to connect to our DC!
DNS update failed!
kinit and wbinfo work without errors and return the correct information. I am also getting the exact same behavior on a RHEL6.2 machine. Any ideas?