Make sure you have all needed dependencies. It seems you are missing spring-instrument jar.
As per the documentation ( http://static.springsource.org/sprin...rence/aop.html especially section 7.8.4 Load-time weaving with AspectJ in the Spring Framework ):
Required libraries (JARS)
At a minimum you will need the following libraries to use the Spring Framework's support for AspectJ LTW:
spring-aop.jar (version 2.5 or later, plus all mandatory dependencies)
aspectjrt.jar (version 1.5 or later)
aspectjweaver.jar (version 1.5 or later)
If you are using the Spring-provided agent to enable instrumentation, you will also need:
Make sure you have all those Jars in your classpath.