Sorry code was lost… Here the examples:
index.php?id=1 activates the corresponding menu-item correctly.
But when the same page is loaded with extra vars, menu-item is not activated:
index.php?id=1&project=5 > menu-item index.php?id=1 not activated
index.php?id=1&project=5&var=foo > menu-item index.php?id=1 not activated