[OS X Emacs] [Aquamacs] CMD + ^ doesn't work in a new nightly

[Moritz Ulrich]

Hello,

I've switched to an Aquamacs nightly (2009-Jul-05) recently.
Since then the shortcut Cmd + ^ (Meta + ^) doesn't work anymore. It
should join the current line with the one above.

I think it's important to mention that I'm on a German keyboard, so
that I have to type ^<space> to actually get '^'. I would get 'ô' of I
would press ^o.
This worked in the latest stable (I think it as 1.8), and stopped working now.

Is there a customization or something to get the old behavior back?

Best regards,
Moritz Ulrich