Usage of Class.getPackage() can cause NPE in AbstractCacheNamespaceHandler

The AbstractCacheNamespaceHandler uses Class.getPackage() on line 77: this call can actually return null under certain circumstances and should therefore not be used. Just derive the package name from the fully qualified class name instead. Interestingly, the same bug was in several Spring Core classes as well for a long time, so you can check there for a solution too Just search for getPackage in this JIRA instance, and you'll see what I mean.
I haven't checked for other cases, but of course if other code also depends on Class.getPackage() that should be fixed as well.