For Vmotion and HA-DRS cluster you need to have shared datastore. VMotion and Cluster (HA and DRS) are supported on shared direct attached storage array on ESX server. Ensure that you provision the same LUN to both the server and create a shared datastore.
Also please ensure that all your hardware are supported by looking at VMware Hardware Compatibility List (HCL). Let me know if this answer your question.
According to VMware HCL, AX4-5 supports FA-AL.
But it doesn't mean we can use AX4-5 as a direct attached storage for ESX HA cluster.
Since AX4-5 DO NOT support ALUA. I am trying to get more precise answer from EMC technical support. However, i'm still waiting for the answer.
If multiple devices can see the same LUN with the same info (LUN ID, etc), then you can use it for vMotion, etc - ALUA doesn't enter into it.
(note - i work for EMC and have experience with this device, but I'm not part of support).