How to continue cloning a Git repository that the download was stopped?

I was cloning a Git repository when suddenly my internet connection failed. So the download was stopped and about 50% of total files was downloaded.

However I cannot continue the download. If I try to do some Pull/Fetch, Git prompts "fatal: destination path '' already exists and is not an empty directory.". The only way that I found was deleting destination folder and download from beginning.

Are there any way to perform an operation to continue the download from the point it was stopped?

I'm using Git on Windows (through installed TortoiseGit-1.5.2.0-32bit.msi + Git-1.7.0.2-preview20100309.exe).

The Restartable clone feature was part of the Google Summer of Code 2009 ideas for git - in the "Projects So Large Your Head Will Spin" section. However, I'm not aware of an implementation.