The doc (reference/sage/combinat/combinat.html) says:
"hurwitz_zeta(s,x,N) returns the value of the zeta(s,x) to N decimals, where s and x are real."
With Sage 5.0 I get:
hurwitz_zeta(3,1,32) = 1.202056903159594285...
hurwitz_zeta(-3,1,32) -> SyntaxError: unexpected EOF while parsing