Yes, you can fool Tivoli easy.  Copy the nslookup executable to nslookup.ORIG 
for example and then touch a file 'nslookup'.  Vi the 'nslookup' file and type 
in one or more lines saying "echo $<machine name & ipaddr>", where <machine 
name & ipaddr> is the typical response for the original nslookup command but is 
the name and ipaddr that Tivoli is expecting (i.e. your install machine.).

Tivoli will then install anything successfully.  I had exactly the same problem 
and this slick little trick worked fine.

Regards,
ken
ken.garst AT kp DOT org