The CLN website links to the GPLv3, but COPYING inside the latest CLN package lists the license as GPLv2 only. In thread that was linked to, the CLN author states that the CLN license is GPLv2 (only).

http://www.ginac.de/pipermail/cln-list/2009-April/000506.html

GPLv2 is incompatible with GPLv3. Thus, the symbolic package is apparently incompatible with octave on all platforms anyway.

--judd