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Class loader problems are commons-logging's fault? Hardly. It is the mixture of a popular project, some unfortunate class loader decisions and the rants of people who might not understand all the implications of the web container class loaders.
Note: the following applies to Tomcat 5.5; later versions of Tomcat store the jar in the same place but change the package name so it is only used by Tomcat itself. See Tomcat 6 class loader reference. However the problems caused by the Tomcat 5.5 implementation continue to affect the perception of Commons Logging.
If you look at the Tomcat 5.5 class loader reference, you will notice that commons-logging-api.jar was put into the bin/ directory and is available through the System classloader. That was the unfortunate decision. The same issue happens BTW with common-daemon. Why does no one complain? Maybe because it is not such a popular project?
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