pkgsrc issues with custom mk.conf

[Gergo Szakal]

Hi again, I have build DF with SMP support on a dual PII-server. I have 
added the following options to mk.conf in order to enable compiling on 2 
CUPs:

WRAPPER_UPDATE_CACHE=no
MAKE_FLAGS+=-j2
MAny pkgsrc packages (i. e. glib) won't build, while commenting these 
options makes the same packages build just fine. Are these options 
disrecommended, or do I have to enable this way of compiling with 
alternate methods?
Thanks in advance for dealing with my countless support questions.