Changes to PATH environment variable require explorer-restart to become effective

ros 0.4.10-RC-29-gf6a9392 gcc dbg lin
Changes to PATH environment variable require a ros reboot to become effective

Reproduction steps
-install git 2.10.0 from rapps
-open a cmd window and type "git"

Expected result
-git binary is found, as its parent was added to PATH during setup
I double-checked: Windows XP SP3 does not need any explorer restart in that scenario.

Observed result
-git binary is not found, until explorer is killed and restarted (or ros was rebooted) to make PATH changes effective