The most recent Java auto-update through OS X (Leopard) is causing some problems with Java Web Start, the program used to launch the MDO Transporter program. If you’ve gone through the update and your Java Web Start is no longer available it means that the update wasn’t completely successful.
Mac OS X Java Update Causing Problems with Java Web Start?
A symptom of this is trying to launch a Java Web Start Application (Transporter for My Docs users) and having it open something that looks like a text file.
Fortunately there is a fairly simple solution to the problem. You can manually re-install the Java Update from this Apple location.
Let us know through the comments here if this doesn’t work for you.