ADNM & Managed clients, need Internet access?

Greetings,

I’ve but the NetServer managed client on a machine that does NOT have connection to the Internet, and I’m seeing Event ID 90s on the machine, with a return code of 0x20000004. I’m beginning to suspect that even with using the ADMN, the client machines need to connect back to the Alwil Software servers for updates. Is this true?