It matters what version of the OS but you can search for named in /etc/rc2.d and probably find what you are looking for.

It should be S72inetsvc where named is started - you may need /etc/named.conf or /etc/named.boot (again, it matters what version came with the OS).

Since there have been some problems with named and security, you would be better off with using the one you built than using the older version that came with the OS (if you are connected to the Internet).