pkg_add: Warning: package `digest-20121220' was built for a platform:
pkg_add: NetBSD/x86_64 6.0 (pkg) vs. NetBSD/x86_64 6.1_RC4 (this host)
===========================================================================
$NetBSD: MESSAGE,v 1.1.1.1 2008/02/14 11:00:13 kefren Exp $

By default dynamips will eat up all your CPU cycles.

In this case you'll have to supply an idlepc value specific to each IOS
version. For more information see:

        http://dynagen.org/tutorial.htm#_Toc176827651

===========================================================================