NPE when Exception.message == null.
…:INFO:oejsh.ContextHandler:stopped o.m.j.p.JettyWebAppContext{/,file:/…/jenkins/war/src/main/webapp/},file:/…/jenkins/war/src/main/webapp/
2013-02-22 14:13:19.914:WARN:oejs.ServletHandler:/
java.lang.NullPointerException
	at org.kohsuke.stapler.Stapler.escape(Stapler.java:933)
	at org.kohsuke.stapler.compression.CompressionFilter.reportException(CompressionFilter.java:69)
	at org.kohsuke.stapler.compression.CompressionFilter.doFilter(CompressionFilter.java:53)
	at org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1338)
	…