Salut jmalo, tu francés es muy bien! First I would install or reinstall the latest apple java update. Go there to do so: http://www.apple.com/downloads/macosx/apple/ (if you are on 10.2 instead of 10.3 you'll have to go deeper in update history). After that , I would clean up all the LW preferences in the directory (exemple) et voilà/library/preferences. Then I would reinstall LW and see if it crashes again. If it does, copy the console log here as may be able to analyse it.

Saludos

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