dhtmlxTree :: Ajax-based JavaScript Tree End user license agreement

dhtmlxTree Standard - GNU GPL: http://dhtmlx.com/docs/products/dhtmlxTree/license.shtml?gpl
dhtmlxTree PRO - Commercial license ($149): http://dhtmlx.com/docs/products/dhtmlxTree/license.shtml?com
dhtmlxTree PRO - Enterprise license ($399): http://dhtmlx.com/docs/products/dhtmlxTree/license.shtml?ent