From your WHM admin home, type "php" into search box and then from that left column select:
Configure PHP and suEXEC
Select suphp from drop-down, then "save new configuration"
Also, I was advise that eaccelerator not compatible w/- suphp, although upon an apache rebuild at some stage I inadvertently re-enabled eacceleerator yet so far haven't seen any adverse affect although currently trying to learn how to change this via httpd.config without having to completely recompile apache (again).