multipath support for IBM v3700 SAS storage

Hello, we bought 2 IBM x3550 server (with 2 sas HBA each) connected to IBM v3700 storage, redundant SAS canisters , so we need to setup multipath for the volume to store VMs. There is some documentation to do this in proxmox 3?. Xenserver work out of the box, but proxmox don't.

Thanks in advance

Best regards.