ESXi 5.1 does resolve the issue, so the Storage Heartbeat Kernel (SHB), is no longer required.  However, with ESXi v5.0 you do not have to delete both VMK ports and start from scratch.  You can unbind the lowest VMK port via the ESX GUI.  Then modify the NICs so that both are active.   Then create a NEW VMK port in that subnet that's is bound to the iSCSI HBA to replace the lowest VMK port used for SHB. 
Dell have just installed a new EQL PS SAN and configured it for our 5 x ESXi 5.0U1 hosts. Each host has 2 dedicated 10GB NICS on a dedicated vswitch for the iSCSi connections to the SAN. MPIO is via the add-on Dell MPIO driver. They are configured in a 1:1 way to 2 VMK ports iSCSi1 ands iSCSi2 as per usual. However since Dell left I have come across a Dell/EQL white paper (TR1075-Configure-iSCSI-Connectivity-with-VMware-vSphere-5.pdf) which says that a separate vmk port should be configured to maintain "pingability" of the iscsi ports during failure/failover. This port should have an ip address on the iSCSi subnet and the 2 10GB nics should be active in the team but not be bound to the sopftware iSCSi adapter. It should also be the lowest vmk port no. The following posts in various net forums seem to suggest this is vital:-  [URL] [URL] [URL]  If it is there it is easy to create the additional vmk but how would I make it the lowest port without deleting the existing ports and interupting SAN access.   Regards,   Gerry
Storage Heartbeat Vmkernal port for Equalogic PS array 