From http://opensource.adobe.com/wiki/display/cmap/License:

Every CMap resource includes the following embedded license information:

%%Copyright: -----------------------------------------------------------
%%Copyright: Copyright 1990-20xx Adobe Systems Incorporated.
%%Copyright: All rights reserved.
%%Copyright:
%%Copyright: Redistribution and use in source and binary forms, with or
%%Copyright: without modification, are permitted provided that the
%%Copyright: following conditions are met:
%%Copyright:
%%Copyright: Redistributions of source code must retain the above
%%Copyright: copyright notice, this list of conditions and the following
%%Copyright: disclaimer.
%%Copyright:
%%Copyright: Redistributions in binary form must reproduce the above
%%Copyright: copyright notice, this list of conditions and the following
%%Copyright: disclaimer in the documentation and/or other materials
%%Copyright: provided with the distribution.
%%Copyright:
%%Copyright: Neither the name of Adobe Systems Incorporated nor the names
%%Copyright: of its contributors may be used to endorse or promote
%%Copyright: products derived from this software without specific prior
%%Copyright: written permission.
%%Copyright:
%%Copyright: THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
%%Copyright: CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
%%Copyright: INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
%%Copyright: MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
%%Copyright: DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
%%Copyright: CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
%%Copyright: SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
%%Copyright: NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
%%Copyright: LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
%%Copyright: HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
%%Copyright: CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
%%Copyright: OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
%%Copyright: SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
%%Copyright: -----------------------------------------------------------

Although the license associated with the CMap resources clearly allows
changes to be made, we strongly discourage changes, especially when they
affect existing mappings. This is for reasons of compatibility. We do
welcome and encourage suggestions for additional mappings.