jackrabbit-webapp and apache-tomcat-8 : Only one repository startup servlet allowed per web-app.
For a long while all fast attempts to try Apache Jackrabbit 2.x on Apache Tomcat™ 8.x failed with a « Only one repository startup servlet allowed per web-app. » error message.
Few months ago I had to make those work together and spend some time to diagnose and fix it. Running it with JPDA DEBUG mode I found that getServletContext().getResourceAsStream(…) has strange behavior. Despite the javadoc states it should return null, it throws an IllegalArgumentException.