A: First, make sure you are passing the fastcgi option correctly, one way to do this is simply:

$ sudo env PKG_OPTIONS.php=fastcgi make install

 
Once that completes, there are now two php binaries on your system.
The cli binary:

$ /usr/pkg/bin/php -v
PHP 4.4.4 (cli) (built: Dec 5 2006 07:12:02)
[…]

A: This appears most commonly seen after an upgrade from NetBSD 2.2 to 3.0.
This is caused by additional copies of libpam being installed, most likely in /usr/pkg/lib via pkgsrc.
You can first check this by simply

$ ls /usr/pkg/lib/libpam*

 
If you find these libraries exist, then you should check the following:
/etc/ld.so.conf

libm.so.0 […]

A: You will need to add the following option to /etc/dhcpd.conf on your DHCP server.

next-server 10.0.0.5;

 
The next-server address should refer to your tftp server.