SEVERE Error Reading Tld Listeners Java Lang Nullpointerexc

Tomcat 5.5を使っていて以下エラーが発生したので、対処する方法を記載しておく。

SEVERE Error Reading Tld Listeners Java Lang Nullpointerexc
SEVERE: Error reading tld listeners java.lang.NullPointerException, the error appears to come from log4j.

参考にしたURL

http://my.opera.com/PrafulShah/blog/2007/04/16/tomcat-5-5-20-severe-error-reading-tld-listeners-java-lang-nullpointerexc

以下抜粋

SEVERE Error Reading Tld Listeners Java Lang Nullpointerexc
SEVERE: Error reading tld listeners java.lang.NullPointerException, the error appears to come from log4j.

I came across this error when reloading a context in Tomcat 5.5.20.

The solution appeared to be to remove commons-logging from WEB-INF/lib of my web app. I'd only added it because Jakarta's HttpClient insisted on it.

Once again, when in doubt, blame commons-logging.

ようは、WEBアプリのcommons-loggingが悪さをしているので、WEBアプリの WEB-INF/libからcommons-logging.jarを取り除いたら、自分もエラーがでなくなった。