Hello, it seems you are right, in ubuntu you can not use this software raid.
but, here in RH: https://access.redhat.com/site/articles/118133 you can see there is HP driver forth to try.
Check download site for your server http://h20565.www2.hp.com/portal/site/hpsc/template.PAGE/public/psi/swdHome/?sp4ts.oid=5249571&spf_p.tpst=swdMain&spf_p.prp_swdMain=wsrp-navigationalState%3DswEnvOID%253D4103%257CswLang%253D%257Caction%253DlistDriver&javax.portlet.begCacheTok=com.vignette.cachetoken&javax.portlet.endCacheTok=com.vignette.cachetoken#Driver - Storage Controller - there is driver which could help.
Check and let us know.
Jan