As noted in
SOLR-3879, Mike's new check in the smoketester found out that Lucene's binary release ships with a servlet-api.jar file in the Lucene demo module. This file is an interface-only file and is provided by the servlet container where you would run the webapp.
This file should be removed from the binary release (the License is also questionable, because the "original" Sun License of servlet-api.jar was CDDL, although thats unimportant because it is an API definition file and not a implementation with actual program code. Shipping any binary code with servlet-api.jar is as wrong as shipping a Java project with JDK's rt.jar bundled).
In general we should (in another issue) restructure our lib folders and differentiate (using IVY configs) between compile-time dependencies and run-time dependencies. Servlet-api.jar is a typical example for a pure-compile-time dep.