Establezca classPath para mysql-confonector.jar

 JAVA_HOME  
 C:\Program Files\Java\jdk1.6.0

 PATH 
 C:\Program Files\Java\jdk1.6.0\bin;

 CLASSPATH
 .;C:\Program Files\Java\jre1.6.0\lib\ext\mysql-connector.jar;.;
Graceful Grivet