This is an Apache 1.1 derived license. Unfortunately, clause 4 is too broad, making it Free but GPL-incompatible.
/* $Id: LICENSE.txt 3117 2006-04-07 15:49:12Z jvanzyl $ Copyright 2002 (C) The Codehaus. All Rights Reserved. Redistribution and use of this software and associated documentation ("Software"), with or without modification, are permitted provided that the following conditions are met: 1. Redistributions of source code must retain copyright statements and notices. Redistributions must also contain a copy of this document. 2. Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 3. The name "classworlds" must not be used to endorse or promote products derived from this Software without prior written permission of The Codehaus. For written permission, please contact firstname.lastname@example.org. 4. Products derived from this Software may not be called "classworlds" nor may "classworlds" appear in their names without prior written permission of The Codehaus. "classworlds" is a registered trademark of The Codehaus. 5. Due credit should be given to The Codehaus. (http://classworlds.codehaus.org/). THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */