First off, my apologies if this issue has already been resolved in some orderly way. If so, I couldn't find the solution anywhere, so maybe a pointer could be added to the wiki. I was in GrinNoCat's situation and tried to make the keypad work. Not to steal your thunder, Greyman, but this I think is beyond the scope of the keymapper.
Anyways, here's this little hack I've come up with. Disclaimers apply: Don't try this if you don't know what you're doing. If trumbles ruin your cargo and eat you alive, or your Mac crashes and burns and destroys all your precious data, don't say you hadn't been warned.
Well, here goes. Not to be able to use the keypad on the Mac bugged me. Badly. To me, it's the only way to fly. With Apple apparently taking the stance that since there are discrete arrow keys, you don't need NumLock, you won't get it: what do we do? We'll need to remap the keypad. But because Oolite appears to eat the keycodes raw, changing the keyboard layout (e.g., using Ukelele) won't help. Apparently, we'll have to do it the hard way.
Looking at different approaches, I came across KeyRemap4MacBook [http://pqrs.org/macosx/keyremap4macbook/
]. A brilliant system extension made by Takayama Fumihiko (tekezo), which allows you to remap any key. (This might help Oathbreaker, too.) Contrary to what the name seems to imply it is not limited to MacBooks. And it already has a NumLock emulation of sorts, albeit without the indicator LED one may be used to. Let me stress it again, this is an unsupported third-party extension Apple support won't want to hear about.
Activating the settings "Use KeyPad as Arrow" under the heading "For PC Users" takes us most of the way.
[attachment=]remap_keypad.png[/attachment] (to be added)
Pitch and roll all you want from your keypad now. Woot! But then, you'll notice that yaw doesn't work yet. In order to make the remapped Num1 (End) and Num3 (PgDn) work as expected, you'll need to modify your keyconfig.plist like so:
key_yaw_left = 304; // end
key_yaw_right = 308; // pgdn
These I found by trial an error, looking at NSEvent.h and counting. Works for me on a PowerMac running 10.4, YMMV.
But that's it, really. Works a treat for me, and I can play Oolite on the Mac as I do on Linux. If it works for you, great. Say thanks to tekezo, and consider making a donation at [http://www.pledgie.com/campaigns/11108