Confused by Maxima 5.9.0

I upgraded from Maxima 5.6 to 5.9.0 and I can't figure out how to 
integrate now. What follows is a sample session.

Thanks,
Shaun


GCL (GNU Common Lisp)  (2.6.1) Tue Jan 27 20:46:38 UTC 2004
Licensed under GNU Library General Public License
Dedicated to the memory of W. Schelter

Use (help) to get some basic information on how to use GCL.
Maxima restarted.
(C1) sqrt( 2 - 2*cos(t));

(D1)                          SQRT(2 - 2 COS(t))
(C2) integrate( %, t, 0, 2*%pi);

       2         2
Is  SIN (t) + COS (t) + 2 COS(t) + 1  positive, negative, or zero?

positive
positive
positive
Incorrect syntax: POSITIVE is not an infix operator
\npositive\npositive\n
                    ^
(C3)