check procedure: 1: rm -r $tomcat/webapps/* 2: rm -r $solr/data ，，，ur index data directory 3: check xml（any xml u modified） 4: start tomcat
i had same error, but i forgot how to fix...so u can use my check procedure, i think it will help you i use tomcat+solr in win2003, freebsd, mac osx 10.5.5, they all work well -- regards j.L
