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I am using Lion on a late 2009 13 inch MacBook, with external monitor and an external Apple Keyboard with numeric keypad - German (MB110D/B) while keeping the MacBook lid closed.
Some of the applications I run use the F-keys. This works fine for F5 and F6 but the other key are used for things like muting and so on.
There is an option in the preferences to use the fn-key in combination with the F-key. Unfortunately the keyboard I am using has no fn-key. Any ideas?