Hi, 

looking at the link : 
ftp://ftp.netbsd.org/pub/NetBSD/packages/pkgsrc/mail/p5-MIME-tools/Makefile
your version of MIME-tools is outdated : 
- new version is : 5.414
- new author is : DSKOLL
- new page is : http://search.cpan.org/~dskoll/

beware you have to run p5-MIME-Base64 3.03 at least (latest in 3.05),
so you'll have to bump this version too. 

Upgrade is really needed for people using products such as
MIMEDefang/amavisd-new/Mailscanner see :
http://search.cpan.org/src/DSKOLL/MIME-tools-5.414/ChangeLog
(bugs, additional features and better detection of evil MIME messages)

A great amount of work has been done by Martin Blapp
(FreeBSD fellow).... 

Regards, 

SL/