Upgrading ESXi 4.1.0 to 5.5

Hi,

I recently got the task of doing an upgrade for a VMWare ESXi 4.1.0 (build 474610) server.

Accoding to the documentation, this upgrade can be done using the VMWare Upgrade Manager.

I was searching for the Upgrade Manager for ESXi 4.1.0 and have noticed that there is an Upgrade Manager 5.5.0 available.

Is this the current Upgrade Manager or is this specifically for ESXi 5.5??

Hope to hear from you guys soon.

Thanks in advance.