All the credit for this post goes to blog commenter – Vincent Wu.
VMware recent released a Knowledge Based (KB) article 2035268 that states support for VMware View 5.1.x with vSphere 5.1. It shows two ways to enable support:
1. You can deploy the updated VMware ESXi 5.1 ISO image. Instructions are in the KB article.
2. You can apply Patch ESXi510-201210001 from the Patch Download Center.
If you are using the Dell Customized Bits for VMware vSphere 5.1, then you will need to apply Patch ESXi510-201210001 from the Patch Download Center in order to support View 5.1.x.