Jar Launcher - Increase Memory Allocation

Hello, I would like to use the Jar Launcher application to run a Java program. The program is quite memory intensive and I would like to increase its maximum memory allocation (by default it is set at 86M).

I can do this on the command line with `java -jar app.jar -Xmx512m'

Is it possible to pass parameters to the Jar Launcher?

(this is a cross-post from http://discussions.apple.com/message.jspa?messageID=11515864)