Problems with Growl notification

[Tony Cebzanov]

I use screen on my Mac, and would like to be able to get Growl
notifications when certain events happen in one of my terminals.  My
terminal emulator (iTerm.app) supports the following control sequence to
display a Growl notification:

echo $'\e]9;Hello, world!\007'

Outside of a screen session, this shows "Hello, world!" in a Growl
message bubble, but inside of screen, nothing happens.  I suspect some
kind of filtering/translation of terminal escape sequences, but I really
don't know for sure.  I can understand why this would not work when a
screen window is in the background (escape sequence wouldn't get to the
terminal app at all) but it doesn't even work in the foreground.

My questions are
1.  Is there anything I could be doing wrong / any settings I can play
with to make this work for the case when the window in question is in
the foreground?
2.  Would it be possible to add support to screen to look for this kind
of escape sequence in background windows and pass it on to the terminal
application?  In this way, background notification via Growl could be
supported.

Thanks.
-Tony