Please have a look at the openmotif license. I do not think, that this
is really a problem:
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2. GRANT OF RIGHTS
The rights granted under this license are limited solely to distribution
and sublicensing of the Contribution(s) on, with, or for operating
systems which are themselves Open Source programs. Contact The Open
Group for a license allowing distribution and sublicensing of the
Original Program on, with, or for operating systems which are not Open
Source programs.
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