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Methods to query the current namespace scope would be useful like getNamespaceForPrefix(String prefix) would return the Namespace declared for the given prefix (or null if the prefix is not in scope). Additionally NamespaceStack should have the ability to push arbitrary Namespace details on to the stack, not just Element and Attribute details.
Fixed in Gordon's stream commit 4521c3b , then merged with the StAXReader/Writer pull #105