Please try Java 7u6 Mac port Plugin
Oracle has created a Java 7u6 Mac port Plugin. It contains the Applet and Java Webstart features that were not available in 7u4 Mac JDK. Please give it a try and let us know how it works for you.
To get the 7u6 Mac port Plugin:
For known issues, please see release notes:
Please report any bugs at http://bugreport.sun.com or post to this thread. We would like to hear both success stories and issues you have encountered.