does anyone know how to find out the bullet version being used for a particular version of houdini?

does anyone know what version of bullet is being used by 12.1.185? is it still bullet 2.77?

All versions of Houdini so far have only used 2.77. The version is listed on the System Requirements page: http://www.sidefx.com/index.php?option=com_content&task=view&id=415&Itemid=269 [sidefx.com]