Log4cpp is the log4j-like logging library used by the OpenSAML and Shibboleth projects.
During the course of Shibboleth development, the original author orphaned the library and a set of patches was locally applied to produce a custom package to correct some thread safety and shutdown issues in the code. The project has since revived but a sync-up has not yet occurred. You MUST use the Internet2-supplied version or you will not have a reliable package.
The locally produced source package is available at http://sourceforge.net/projects/log4cpp/files/
For now, refer to the BuildingShibboleth topic for build notes.