port register/unregister hogs up resources and takes forever

[Arnt Gulbrandsen]

That's one strange-looking strace. Makes me wonder if some text file has 
been corrupted. Could you perhaps run "find /var/db/pkg -type f -print 
| xargs file | grep -v text"?

Do any files in /var/db/pkg contains lots of 0xD0 bytes?

Arnt