How correctly build php subpackages from ports ?

[irix]

When I try to build one or two subpackages for php 5.3 or 5.2, system 
try to build all available subpackages with their dependences. How I can 
avoid this ?

I login to /usr/ports/lang/php/5.3  and make show=MULTI_PACKAGES this 
show me list available options and when I try to use: env 
SUBPACKAGE="-fpm" make install
System build and all subpackages. Iwas very puzzled by this behavior.