mime-play-delete-file-immediately: recent changes? (also Cocoa Emacs link question)

[John Owens <wl2.20.jowens@spamgourmet.com>]

I recently updated from a ~winter-spring 2010 WL build to a
top-of-tree build. One thing that's changed is that when I launch an
attachment with 'v', it no longer works; the file is not found. The
setting that is supposed to control this is:

(setq mime-play-delete-file-immediately nil)

but it appears the behavior has changed between my previous build and
this build. Any idea what might have happened?

On another note, I'm now using OS X emacs 23 (the cocoa build).
Previously I used the carbon emacs 22 build. On carbon emacs, I could
option-click links in messages; I believe this was equivalent to a
middle-click and would launch them in the browser. This no longer
works in cocoa emacs; anyone have any thoughts on this?

JDO