After several hours playing whit java install /uninstall , I found a solution .
But a VERY strange solution . Someone told me to run ClearType Tuner
http://www.microsoft.com/windowsxp/Downloads/powertoys
/Xppowertoys.mspx
It's a utility of the 'powertoy tool' from microsoft to adjust the way the text is displayed on the screen.
It has nothing to do with java but it's working ...