[Maxima] Limit is wrong

[Richard Hennessy]

try,

(%i1) signum(limit(subst(inf,x, a*x^2)));

sign: sign of infinity is undefined.
 -- an error.  To debug this try debugmode(true);
(%i2)

This is another bug, present in 5.18.1 and 5.19.0.  In the limit the sign does matter.  I think it is incorrect for limit to give an 
answer of "unsigned" infinity.

Rich