Unexpected exception when activating MATLAB R2009a or earlier on Mac Pro

http://www.mathworks.com/support/solutions/en/data/1-8GS5S1/index.html

Subject:

Why do I get an unexpected exception when activating MATLAB 7.8 (R2009a) or earlier on a Mac OS X machine?

Problem Description:

When I attempt to activate MATLAB on Mac OS X, I get the error:
There was an unexpected exception:
null
See the log file (/tmp/aws.log) for more details.
The log file has the following information:
MATHWORKS ACTIVATION IS STARTING UP.
java.lang.UnsatisfiedLinkError: Cant load library: /Applications/MATLAB_R2008b.app/bin/maci64/libinstutil.jnilib
com.mathworks.instutil.NativeUtility.(NativeUtility.java:36)
com.mathworks.instutil.MachineInfo.(MachineInfo.java:40)
com.mathworks.activationclient.model.ActivationModelImpl.loadNativeLib(ActivationModelImpl.java:216)
com.mathworks.activationclient.model.ActivationModelImpl.getMachineInfo(ActivationModelImpl.java:189)
com.mathworks.activationclient.view.ApplicationViewImpl.getMachineInfo(ApplicationViewImpl.java:200)
com.mathworks.activationclient.view.ApplicationViewImpl.showGUI(ApplicationViewImpl.java:79)
com.mathworks.activationclient.controller.ApplicationControllerImpl.start(ApplicationControllerImpl.java:99)
com.mathworks.activationclient.ActivationApplication.main(ActivationApplication.java:31)
null
com.mathworks.activationclient.view.ApplicationViewImpl.showGUI(ApplicationViewImpl.java:79)
com.mathworks.activationclient.controller.ApplicationControllerImpl.start(ApplicationControllerImpl.java:99)
com.mathworks.activationclient.ActivationApplication.main(ActivationApplication.java:31)
How can I activate MATLAB on Mac OS X?

Solution:

This issue is due to a change in the default Java version from when MATLAB R2009a was released. The activation may attempt to call 64 bit libraries, whereas MATLAB is a 32 bit application under Mac OS X. As a workaround, you can temporarily change your system's default java for applications to use the 32-bit JVM. Once you have activated, you can change it back to Java 6 (64-bit) or J2SE 5 (64-bit).

To do this, open the Java Preferences application from /Applications/Utilities/Java/Java Preferences (early 10.5 releases) or /Applications/Utilities/Java Preferences (10.6).

Make sure you are under the "General" Section, and if there are multiple lists, the "Java Applications" list will be modified. In the section marked "Java Applications", drag the 32-bit item to the top of the list. Then close this application and restart the activation client by double clicking on the MATLAB application in your Applications directory.