following RELENG_6_1

[Thierry Lacoste]

I have a bunch of servers running FreeBSD 6.1-RELEASE.
They perform crucial tasks like Samba domain control, LDAP directory, mail, 
etc...
Though I'm reluctant to touch them I feel that the recent Security 
Advisories
(especially about ssh ans ssl) are a very good reason to follow RELENG_6_1.

I'd be grateful if someone could answer the following questions.

Is it possible that an upgrade might break software installed from the port?

I'm planning to use a build machine as explained in "Tracking for Multiple 
Machines"
http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/small-lan.html
What are the alternatives? Is there an easiest yet safe way to go?
I was interested by /usr/ports/security/freebsd-update but some of my 
kernels
have "options QUOTA" so I guess it rules out freebsd-update.

Quoting FreeBSD-SA-06:23.openssl
> NOTE: Any third-party applications, including those installed from the
> FreeBSD ports collection, which are statically linked to libcrypto(3)
> should be recompiled in order to use the corrected code.
How can I find the applications which fall in this category?

Best regards,
Thierry.