Or even better solution that takes into account "Enter, click, dblClick":
function beforeedit(editor, context, eOpts)
{
editor.grid.needToClear?context.value="":{};
}
function beforeitemkeydown(sender, record, item, index, e, eOpts)
{
var me=sender.grid;
me.needToClear = (e.getKey() !== 13);
}
function beforeitemkeypress(sender, record, item, index, e, eOpts)
{
var me=sender.grid;
me.editingPlugin.startEditByPosition({
column: me.uniCol,
row: me.uniRow
});
}