Following extensive discussion on license-discuss and with the OSI board about click-wrap and other mechanisms for manifesting assent to licenses, I have added a new first sentence to section 9 of the Open Software License. Only the first sentence is new.
9) Acceptance and Termination. If You distribute copies of the Original Work or a Derivative Work, You must make a reasonable effort under the circumstances to obtain the express and volitional assent of recipients to the terms of this License. The rest of this section 9 and the OSL can be found at www.rosenlaw.com/osl1.1.html. /Larry Rosen -- license-discuss archive is at http://crynwr.com/cgi-bin/ezmlm-cgi?3