Yes that's true, unfortunately we only have 3 modifier keys (Shift, Ctrl and Alt) on standard keyboards... I thought it's preferable to use those precious keys for production application than for manipulating desktop functions. But we should neverthless add a note in the doc for people wanting to change the default desktop shortcut. I'll do that right now, thanks for bringing up the issue.
Yorik van Havre São Paulo Brazil http://yorik.uncreated.net
In a part on the manual:
states that "in some tools ALT will give you extra options"
please remember that holding this key on linux and clicking, will move
the entire window as it is an standard binding of every window