separate-git-dir doesn't work with mapped drive

Hi

I want to use git in a VirtualBox guest so that the repository is on the host drive. So in the VB settings for the guest I set up a shared folder "gitRepos" to /home/ain with full access rights. Then in the guest OS (Windows XP) I map this shared folder as G drive. Now in the project dir I execute

C:\...\TPP>git init --separate-git-dir g:/TPP Initialized empty Git repository in g:/TPP/

Checked, the repo structure is in the "g:/TPP/" (thus the guest OS can write to the mapped dir) and in the .git file created to the project dir there is line

gitdir: g:/TPP

However when tring to use the repo it fails to recognise the g:/TPP path, ie

C:\...\TPP>git add . fatal: unable to access '../../../../../../g:/TPP/config': Invalid argument

Also tryed "gitdir: //VBOXSVR/gitRepos/TPP" but this fails too:

C:\...\TPP>git add . fatal: Unable to create 'C:/Documents and Settings/Ain/prog/AVT/TPP/../../../../../..///VBOXSVR/gitRepos/TPP/index.lock': No such file or directory

Am I doing something wrong or is it a bug? Any idea how to get it to work?

BTW the VB is 3.0.14 ie rather old version but it seems that this isn't the problem as the git init recognises the mapped drive but other commands fail. git version is 1.8.4.msysgit.0

TIA ain