yup, that interface has been deprecated, and on top
of that, won't work any more.
The WLS 9.x and later JavaDocs reads:
Replaced by standard JMX design patterns in which clients use the javax.management.MBeanServerConnection interface to discover MBeans, attributes, and attribute types at runtime.
Maybe having a look at
Accessing WebLogic Server MBeans with JMX helps.
[ August 25, 2008: Message edited by: Matt Cartwright ]