FWIW, I can't get it as a package either:  

bsd: {8} pkg_add ftp://ftp.be.netbsd.org/pub/NetBSD/packages/1.6.2/i386/mail/spamassassin-2.63nb1.tgz
pkg_add: no pkg found for 'p5-HTML-Parser-3.35', sorry.
pkg_add: 1 package addition failed
pkg_add: autoload of dependency `p5-HTML-Parser-3.35' failed!
pkg_add: no pkg found for 'p5-HTML-Parser>=3.29', sorry.
pkg_add: 1 package addition failed
pkg_add: autoload of dependency `p5-HTML-Parser>=3.29' failed!
pkg_add: no pkg found for 'p5-HTML-Tagset-3.03', sorry.
pkg_add: 1 package addition failed
pkg_add: autoload of dependency `p5-HTML-Tagset-3.03' failed!
pkg_add: no pkg found for 'p5-HTML-Tagset>=3.0', sorry.
pkg_add: 1 package addition failed
pkg_add: autoload of dependency `p5-HTML-Tagset>=3.0' failed!
pkg_add: no pkg found for 'p5-IO-Socket-SSL-0.95nb1', sorry.
pkg_add: 1 package addition failed
pkg_add: autoload of dependency `p5-IO-Socket-SSL-0.95nb1' failed!
pkg_add: no pkg found for 'p5-IO-Socket-SSL>=0.92', sorry.
pkg_add: 1 package addition failed
pkg_add: autoload of dependency `p5-IO-Socket-SSL>=0.92' failed!
pkg_add: no pkg found for 'p5-Net-DNS-0.46', sorry.
pkg_add: 1 package addition failed
pkg_add: autoload of dependency `p5-Net-DNS-0.46' failed!
pkg_add: no pkg found for 'p5-Net-DNS>=0.29', sorry.
pkg_add: 1 package addition failed
pkg_add: autoload of dependency `p5-Net-DNS>=0.29' failed!
pkg_add: no pkg found for 'p5-Net-SSLeay-1.25nb2', sorry.
pkg_add: 1 package addition failed
pkg_add: autoload of dependency `p5-Net-SSLeay-1.25nb2' failed!
pkg_add: no pkg found for 'p5-Net-SSLeay-[0-9]*', sorry.
pkg_add: 1 package addition failed
pkg_add: autoload of dependency `p5-Net-SSLeay-[0-9]*' failed!
pkg_add: 1 package addition failed
bsd: {9} 

Please help.

-- 
Drowning in spam