How do I setup a forward zone in DNS Express, importing from Infoblox

I have some forwarding zones in my internal dns. These zones only contain name server records. When I try to import them into my GTM (2000 hardware, running version 11.4.1) the ltm log tells me the following in var/log/ltm (zone name and ip of infoblox changed to protect the guilty :) )

Jun 2 09:50:47 an-dns1 err zxfrd[6012]: 01531010:3: Transfer of zone xxxxx.net failed b/c there are no records. Jun 2 09:50:47 an-dns1 err zxfrd[6012]: 01531015:3: Failed to retrieve next RR in XFR for zone xxxxxx.net. Jun 2 09:50:47 an-dns1 err zxfrd[6012]: 01531018:3: Failed to transfer zone xxxxxx.net from 1.1.1.1, will attempt AXFR.

Does anyone know how I might accomplish this? I really would prefer not to run bind on these engines, since I have the infoblox engines to do that....