For FreeBSD if you want to run virtualbox-ose-4.0.8, netbeans-6.9.1 and anything else of 2011 you are force to use perl-5.12.3 and python27-2.7.1_1 and perl needs libutil.so.9 which comes in FBSD-9.0 .. so basically GNOME is being murderized and left behind with FBSD-8.2. So
J65nko is right, jail is the only way or a darn good hack... Since we have no choices, I rather hack and I think I'm learning how to build a jail from ground up.
Heres a brand new manual and is very good. Fifteen chapters ... a page for BSD and the rest for Windows and LINUX, as usual. FreeBSD is building a new manual too.
http://www.virtualbox.org/manual/ch04.html#idp11332240
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