If packages are in the javax namespace, they don't follow the ordering in http://tomcat.apache.org/tomcat-5.5-doc/class-loader-howto.html#Class_Loader_Definitions

The build-jar-repository script called in %postinstall of tomcat5-common-lib causes a number of jar files to be put into common/lib, and some of these are in that namespace.

This causes problems, because some of the packages (like the one providing javamail) are too old for many web apps, and there's no clean workaround.

For example, Atlassian Jira recommends this: 
http://confluence.atlassian.com/display/JIRA/Configuring+JIRA+to+Send+SMTP+Mail#ConfiguringJIRAtoSendSMTPMail-MovetheJavaMailClasses 

But the problem certainly isn't limited to Jira.

Please don't put jar files in common/lib unless they are in the default list given by Tomcat at http://tomcat.apache.org/tomcat-5.5-doc/class-loader-howto.html#Class_Loader_Definitions.


Thanks.