External Paste on 1.5.0rc1 on OS X

[Yaron Y. Goland]

Once upon a time external paste would work via a special external paste 
option. I read the docs for 1.5.0rc1 and saw that now the middle button 
is to be used for pasting. Of course by default there is no middle 
buttons in OS X land but I have a multi button mouse and I used USB 
Overdrive to configure how it works. I took one of my extra buttons and 
configured it to be the middle mouse button, the fourth mouse button and 
the fifth mouse button (as defined by USB overdrive) without much joy. 
Setting the extra button to be the 'middle mouse button' did cause LYX 
to paste but it pasted from its internal buffer rather than from the 
external one.

Is there a keyboard shortcut for external paste? Is there a known 
setting to get external paste working on OS X using USB Overdrive?

        Thanks,

                Yaron

P.S. I did try to internet search for a solution and I checked the mail 
archives but I couldn't find anything. I also checked the bug list for 
1.5. I'm sorry if this question has already been answered but I tried my 
best to find that answer and failed.