git describe --tags --long barfs on new tags?

Howdy folks,

Discovered this today:

~/git[master]$ git tag mb
~/git[master]$ git describe 
v1.5.6.1-156-ge903b40
~/git[master]$ git describe --tags
mb
~/git[master]$ git describe --tags --long
Segmentation fault (core dumped)

Hope this is useful info.

BTW - just started using git and I am very impressed with it - took me a while to get my head around the "index" but now I wonder what the problem was.

Cheers,

Mark