Development of the Creative Commons Sampling license (or license option)

[Ricardo Velasco <iskepsis AT gmail.com>]

We have a document covered under this license (http://creativecommons.org/licenses/by-nc/2.5/).  Currently we are seeking permission to use certain images in said document.  My question is, does the permission given to us also cover those who change it?  In other words does the permission cover any and all permutations of the document?

My concern is that often permission is granted for a document which is for educational use, which this document is, but that same document could potentially be changed by another user into something not for education use.

Thank you