net/mtr broken without ipv6

[sib at tormail.org]

Hi. I build my custom kernel without IPv6 since I'm not going to be using
it any time soon. The mtr port doesn't work anymore, no matter what I try.
It was built with and without the IPv6 option checked in 'make config' and
I tried with the -4 option so it shouldn't even be using IPv6. I always
get:

Unable to allocate IPv6 socket for nameserver communication: Protocol not
supported

What can I do to fix this without enabling a useless (to me) option in my
kernel and rebuilding?