hostname() not giving useful results

[kee nethery]

On Mac OS X, on my personal machine, when I do hostname() I get the  
text that is located at:
System Preferences
Sharing
Services
the field labeled "Computer name"
which for me is kee.kagi.com

On another machine at a colo, when I do hostname() I get the machine  
name shown in the text under that field:
"Other computers on your local subnet can access your computer at  
pima-kagi-com.local"

So on one machine I get a useful domain name that the external world  
can use when hitting a DNS, and on the colo machine I get a name that  
is only useful on that local subnet.

Why is there a difference?
How do I get a useful domain name for the colo machine?

Thanks, Kee Nethery