php-mhah appears broken in 3.5 and 3.6

[Tim Howe <tim_(_at_)_deschutesdigital_(_dot_)_com>]

Using a test php page (code can be viewed here:
http://shrike.nmedia.net/ex.phps) php-mhash returns a string of zeros as the
hash value for anything (output is here: http://shrike.nmedia.net/ex.php).  I
have tried this on two different 3.5 installs and on a 3.6 install.  I have also
confirmed my results through another person who has 3.6 installed.

I don't know if it's an mhash issue or an issue with the php extension port.  No
error messages appear in Apache logs.

Anyone else see this or have a work-around?

--TimH