Application does not run on Mac

[Kudret Serin]

Hi all,
I developed a desktop application (with GUI) with Netbeans 6.5
I created a jar for distribution and delivered to the customer.
My customer says that the application runs fine in PC, but it does not run in Mac.
His note about this:

The application works fine on my PC, but I cannot get it to launch on my Mac. What happens is that the Java Coffee Cup symbol appears in the application dock at the bottom of the screen, but disappears after a few seconds. The application's user interface never comes onto the screen.

I do not have a chance to make test on Mac.
What can be the reason? On which points should I focus?

Thanks in advance for any suggestions.

[Rob Spoor]

Can you ask the customer to open the file from the command line? Probably an exception is thrown that crashes your application.