It looks like the second comment on this page may be for you to fix:
http://code.google.com/p/berkelium-sharp/issues/detail?id=1#c2
A shift click seems to work just fine to highlight the text, so if you send a shift down with the down button and a shift with the up button, it will select the text with it when the user drags.
Iβm not sure if this will affect things like choosing a few options on the list, but if you donβt have the type of things on the site that you are trying to support, itβs the thing. I can't think of any other adverse effects right now, but I'm sure some probably exist.
This user says that it worked for him, so take a picture.
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