Concurrent Hierarchical State Machine
CHSM/Groovy is under a BSD-style license. All of CHSM, including the run-time libraries, in particular the chsm.jar, is under the GNU General Public License (GPL). CHSM/Groovy uses the chsm.jar.
The authors of CHSM have relicensed the chsm.jar under a BSD-style license when (and only when) used as part of the run-time for CHSM/Groovy.
Therefore you, as an end user, can use the chsm.jar (only when built from the original, unmodified, CHSM source) under a BSD-style license when (and only when) used as part of the run-time for CHSM/Groovy.
If you want to use a chsm.jar built from modified CHSM source, and those modifications are not under the GPL, then you can no longer use a BSD-style license and must instead revert to using the GPL.
If you have any questions about the licensing, please contact us.