I tried running the 1.7 beta on Mac OS X and the only thing that happens is the icon shows in the Dock. I also get this console message.

Activating Lightweight Aqua Look and Feel
[LaunchRunner Error] com.limegroup.gnutella.gui.Main.main(String[]) threw an exception:
java.lang.ExceptionInInitializerError: java.util.MissingResourceException: Can't find bundle for base name MessagesBundle, locale en_US
at java.util.ResourceBundle.throwMissingResourceExcep tion(ResourceBundle.java:712)
at java.util.ResourceBundle.getBundleImpl(ResourceBun dle.java:683)
at java.util.ResourceBundle.getBundle(ResourceBundle. java:559)
at com.limegroup.gnutella.gui.dc.<init>(dc.java:57)
at com.limegroup.gnutella.gui.dc.<clinit>(dc.java:22)
at com.limegroup.gnutella.gui.bo.<init>(bo.java:124)
at com.limegroup.gnutella.gui.bo.<clinit>(bo.java:40)
at com.limegroup.gnutella.gui.Initializer.b(Initializ er.java)
at com.limegroup.gnutella.gui.Main.main(Main.java:16)
at java.lang.reflect.Method.invoke(Native Method)
at com.apple.buckyball.app.LaunchRunner.run(LaunchRun ner.java)
at java.lang.Thread.run(Thread.java:496)

I'm running Mac OS X (10.0.4) and have installed the Java 3.1 Developer Preview 2 for Mac OS X which includes Java 2 SE 1.3.1. This was released on June 27 and is available as a free download if you register at http://developer.apple.com

I think I can downgrade to the 1.3 version of java with a little (maybe a lot) of effort as the 1.3 files are still installed on the system. Let me know if I should try that.