Failover with (only) MPIO for different hosts

Is it possible with open-e DSS to create the following;

We have two storage servers that are supposed to work in active-passive configuration. We also have two 'virtualisation' servers that are running VMWare ESXi and will request data from the currently active storage server using iSCSI. Should the active storage server fail, the passive server should become active.

I've already managed to create this environment with the failover functionality in DSS. But i'm currently researching if this is also possible with MPIO (in Microsoft's iSCSI initiator or the VMWare ESXi iSCSI initiator) alone. Is it possible to create the same iSCSI target on both storage servers and configure multipathing on both initiators for both paths (one active, the other passive)?

I'm aware that mpio is normally used to allow multiple paths to the same host, but i cannot find any information whether or not it is possible to have multiple paths (to the same target) on multiple hosts. Of course, the contents of the targets should be replicated across the targets. Is this possible with Open-E's iscsi implementation? Or this is not possible at all (and a misunderstanding of mpio on my part)?

I know that VMware has MPIO capabilities with Fiber Channel but as I remember from VMware that this will be in there next release 4.0. There may be some discussion on how to do this with some ESX config but we don't know.

We know that Virtual Iron has this capability but there is some work that has to be done.

MPIO with let's say a MS initiator works well with 2 NIC's and separate subnets to one Target/LUN. We do not support multiple hosts connecting to the same target, you would need a SAN file system.

Is there a procedure for using MPIO with the MS iSCSI initiator (i.e. different subnets)? We have a customer who's trying it right now, and he needs help. Right now, he tried it using the same subnet and it's just using one NIC.

It is because name duplication problems. It can cause problems with access and domain connections especially when Windows based systems are present in the same subnetwork - even though the question is related to MPIO.