Error while installing eclipse for Android

Hello Friends,
I m getting an error"Android DDMS" will be ignored because it is already installed.
                          "Android Development Tools" will be ignored because it is already installed.
                          "Android Hierarchy Viewer" will be ignored because it is already installed.
                          "Android Traceview" will be ignored because it is already installed.
while installing Eclipse For Android....Please do revert back with the solution if anyone can solve the problem...