On the demos I have done for my Lotusphere 2009 session is a demo on how to use the extension point to extend the preferences dialog box (File/Preferences…) in Notes 8. As always a demo makes it easier to comprehend so download and explore to your heart’s content. Questions are welcome here or at Lotusphere.
Otherwise I recommend the Eclipse User Settings FAQ
lekkimworld.com 
Hi Mikkel
I tried to run this package using Eclipse 3.2.2 and Expeditor 6.1.2 but the process stops with an error message:
"Failed to login CLFRJ0010E: Notes Initialization failed."
Or maybe I should not be able to do this?
Best regards from Ove
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You should be able to. This error is normally displayed when another instance of Notes is already running when Notes is launched from Eclipse.
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Do you know anyway of checking what categories exist already in Notes – in particular, I just want to add on to a particular preference section that exists…
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