Since 12th May, the nightly build of the log tablib in http://jakarta.apache.org/builds/jakarta-taglibs/nightly/projects/log/ has dropped in size from 133k to 46 bytes, and is empty. There may be other taglibs similarly affected, as I notice the combined binary builds also dropped in size on the same day, from 4.9M to only 2.8M. Also, when deploying the log-doc.war web application from the combined build of the 11th May, it is described in the web.xml deployment descriptor as the "IO Taglib Documentation" application. I don't know if it's related, but on the Log taglib web page at http://jakarta.apache.org/taglibs/doc/log-doc/intro.html the "Download Log Tag Library" link appears to be pointing instead to the IO taglib's directory.
The nightly build problems have been resolved.