Syntax to set Round Robin to default

Everytime I add new LUNS to my ESXi 4.1 clusters I have to run the below command to change the path policy to RR vs FIXED.   Is there a command I can run that will make the host set all new LUNS path policy to RR as default?

Get-VMHost hostname_here | Get-ScsiLun | Where {$_.CanonicalName -like 'naa.5000*'} | Set-ScsiLun -MultipathPolicy "RoundRobin"

Thanks