Following classes remain:
src/java/org/apache/cocoon/components/modules/input/AbstractMetaModule.java
src/java/org/apache/cocoon/components/modules/input/ChainMetaModule.java
src/java/org/apache/cocoon/components/modules/input/LocateResource.java
src/java/org/apache/cocoon/components/modules/input/XMLFileModule.java
src/java/org/apache/cocoon/components/modules/input/XMLMetaModule.java
=> could imagine that someone wrote his own input module
src/java/org/apache/cocoon/matching/modular/CachingRegexpMatcher.java
src/java/org/apache/cocoon/matching/modular/CachingWildcardMatcher.java
src/java/org/apache/cocoon/matching/modular/WildcardMatcher.java
=> ??
src/java/org/apache/cocoon/transformation/AbstractDOMTransformer.java
=> fear extensions
