Once again MAC has sabotaged it's relationship with Java.
For those poor soles trying to get through life on the newest Snow Leopard, you're probably already used to the Terminal fixes!
It turns out that Java's Serial Library is broken in Java 6 that was installed with this update. you'll need to revert your Java version.
Here's a link to a great tutorial on exactly how to do it:
http://wiki.oneswarm.org/index.php/OS_X_10.6_Snow_Leopard
Start at "Workaround for connection problem"
This is verified here at my house, but was not needed on my 10.6.1 Hackintosh.