Netbeans built .jar for Mac

[zobelogne]

I have an application that is built in Netbeans and on several Widows machines the jar runs fine when it is double clicked. I asked a friend to test it on their Mac and they got an error.

"The Java JAR file 'nameOfJar.jar' could not be launched. Check the console for possible error messages"

My questions are:

What is the console that this message is reffering to?

Is there something I have to set up in Netbeans for the .jar to be executable on Mac?

[Norm]

Are the same or compatible versions of java being used?
I don't know of any options for executing a jar on a Mac.
I've been suprised several times when I gave a program in a jar to a friend with a Mac and it worked. I was on Win98. The same program given to another Windows user required some fiddles on his PC.
Does your code do any OS dependent things. File paths with C: for example.

[zobelogne]

I'm using JDK 1.6, not sure what they're using but will ask them.

There are no hard coded paths in my code. There is some file IO using jFileChooser, but it requires no external files or libraries to run other than the classes included in the jar.