As noted on sage-support, the sage-5.0 *binary* requires the boost
library libboost_unit_test_framework at runtime, if the binary was built
on such a machine. I.e. PolyBoRi checks for boost_unit_test_framework
and links against it if available.
This is because of the PolyBoRi upgrade to version 0.8.1. The older
PolyBoRi in sage-4.8 did not do this.
Ticket created: http://trac.sagemath.org/sage_trac/ticket/12963