Can't install on a clustered DB?

I'm trying to install EP6 SP2 and it fails when attempting to install the Database Schemas on my clustered SQL Database. I can't find ANYTHING ANYWHERE on how to fix this. HELP! Anyone else done this?!

The installation keeps failing due to the fact that it's looking for a local install of SQL Server, but we have a clustered SQL install - how can I tell SapInst to use the cluster, rather than a local SQL Server??

Thanks!

-Eric