What you want, is that those two modules are loaded at boot.
The way to do it is somewhat distribution spesific. In debian you would put lines
to /etc/modules. In gentoo there is /etc/modules.autoload.d/kernel-2.4 that contain the same information in same format.
If your distribution doesn't have such file(s), you could try to look for a file called /etc/rc.local. If it exists, it is ran at the end of the boot and you could put those modprobe-lines there.