The problem is:
Code:
===> firefox-2.0.0.20_9,1 has known vulnerabilities:
=> mozilla -- multiple vulnerabilities.
Reference: <http://portaudit.FreeBSD.org/49e8f2ee-8147-11de-a994-0030843d3802.html>
=> Please update your ports tree and try again.
Ports refuse to install when there are known vulnerabilities.
Did you try the suggestion in the last line? (Update ports tree and try again).