Okay, I thought sombody else knows better than me. So here goes:
Somewhere below /etc(/init.d) you'll find directories like rc.d1 rc.d3 etc. The number means the runlevel. In these directories there are links to the actual modules which are in some manner numbered (somthing like module17) the number determines the sequence the modules are loaded. So you can rename ipchains99 to ipchains00 at your own risk
to get it loaded first in the runlevel you use.