[mod_python] weird request.connection.remote_ip value

I'm running mod_python 3.2.8 on Mac OS 10.4.6, python 2.4.3, apache  
2.2.2, on my desktop machine.

I've got apache set up to load this script:

========================= begin

from mod_python import apache

def handler(request):
     request.write(request.connection.remote_ip)
     return apache.OK

========================= end

When I browse to "http://127.0.0.1/", the script prints out  
"127.0.0.1" as expected.

If I connect from a local network, e.g. to "http://192.168.0.6/" it  
prints out "192.168.0.4" (the address of the other machine) as expected.

But when I browse to "http://localhost/" from this machine, it prints  
"::1".

What does "::1" mean? Why isn't it giving me an IP address? Shouldn't  
I be getting "127.0.0.1" as above? How can I guarantee to get an IP  
address?

Thanks

David