From uni software plus GmbH:
MathLink for AppleScript is a Scripting Addition (OSAX) that makes it possible to use Mathematica as a computational engine in AppleScript programs. The second use of MathLink for AppleScript is to allow external functions written in AppleScript to be called from within the Mathematica environment. This makes it easy to extend Mathematica with functionality provided by AppleScript enabled applications.
Mathematica 5.2 compatibility
The scripting addition has been linked with latest version of the MathLink library (part of Mathematica 5.2).
new command "MathLink peek"
The "MathLink peek" command peeks ahead one expression on a link without consuming it.
AppleScript Studio support
A sample AppleScript Studio based application titled "Plot" has been added to the examples. This is a simple function plotter that uses the MathLink scripting addition to render function plots with the Mathematica kernel.