[CentOS] How and when are the sound modules loaded at system boot time on CentOS 5?

Mon Feb 7 17:38:33 UTC 2011
James Pearson <james-p at moving-picture.com>

I've been trying to work out how the various sound modules get loaded at 
boot time on CentOS 5 - but I can't find anything obvious under /etc/rc.d/

CentOS 4 did this in /etc/rc.d/rc.sysinit - but there is nothing 
equivalent in CentOS 5

Does anyone know how these modules get loaded?

Thanks

James Pearson