git submodule update command fails on Ubuntu 12.04

[jsavage]

Error message from sudo -E git submodule update was:

fatal: unable to connect to git.sv.gnu.org:
git.sv.gnu.org[0: 140.186.70.72]: errno=Connection timed out
Unable to fetch in submodule path 'dependencies/autoconf-2.69'

The url in last line of .gitmodules seems incorrect as I cannot browse to it.

so i tried changing this to:
url = http://git.savannah.gnu.org/r/autoconf.git

Now I get the following error from git submodule update

fatal: Needed a single revision
Unable to find current revision in submodule path 'dependencies/autoconf-2.69'

I get the same error if I use the git:// protocol in the above URL too

Any ideas on a solution would be welcome.

James