Installing port without dialog boxes?

[List Admin]

I just reinstalled freebsd 5.3 on my machine and I wish to install Gnome
next.  Since it takes about 4 days to install on my slow machine, could
someone please tell me how I could do an "unattended" install?  I hate
looking over at the machine after 8 hours of install only to find a
dialog box asking me configuration information.

Thank you,
Thomas