looking at making Maxima's solve program more robust, maybe along the
lines of Mathematica's Reduce, I came up with this simple problem,
solve((x-%pi)/sin(x)=0, x)
which Maxima says has the solution x=%pi,
which is (a) false in that it reduces to 0/0=0 by substitution, and
(b) false in the limit as x->%pi, since it is then -1=0.
Mathematica 6.0 gives a warning in that a potential solution was
"possibly discarded by verifier" and
should be check by hand. May require use of limits.
It also warns that inverse functions are being used by Solve, and
suggests using Reduce.
RJF