Error occured while launching SwingSet2 demo

Tested OS : Solaris Sparc

Steps to reproduce :
Install jdk1.6.0 build15 using jdk-6_0-ea-bin-b15-solaris-sparc-09_dec_2004.sh
Go to jdk1.6.0/demo/jfc/SwingSet2
Launch SwingSet2 demo using java -jar SwingSet2.jar

Actual Behaviour : There is no Button Demo. Also following error occured in the prompt "Error occurred loading demo: ButtonDemo"

Expected Behaviour : There should not be any error and Button Demo icon should be present

Note : This behaviour is inconsistent
###@###.### 2004-12-17 14:16:28 GMT