The goal of this project is to get NHibernate.Search compiled against .Net4 and newest dependencies BTW, you get .Net4-compatible NHibernate for free. I've gathered sources of most of the NHibernate.Search's dependencies and provided a common VS2010 solution to compile them all. WARNING: Sources contain my patches to make them work together and compile on .Net4. I'm working on getting these patches into main dev branches of the respective projects. Hibernate changes: Iesi.collections: .Net4's System.Collections.Generic compatibility HQL handling: Parsers regenerated with newer version of antlr3 Sources fetched from: log4net: https://www.apache.org/dyn/closer.cgi/logging/log4net/source/log4net-1.2.11-src.zip Lucene: https://www.apache.org/dist/incubator/lucene.net/source/2.9.4g-incubating/ NHibernate: http://sourceforge.net/projects/nhibernate/files/NHibernate/3.3.0CR1/ NHibernate.Search: http://nhcontrib.svn.sourceforge.net/viewvc/nhcontrib/trunk/src/NHibernate.Search/ @ r1683 Antlr3: http://www.tunnelvisionlabs.com/downloads/antlr/antlr-dotnet-source-3.4.1.9004.7z ReMotion: https://www.re-motion.org/builds/Remotion_1.13.144.zip