What happens when you run these commands:
To view the current build number of the VMX component of the ESX Server installation:
<div class="MsoNormal" style="margin: 0pt">1. Log in to the ESX Server Service Console .</div><div class="MsoNormal" style="margin: 0pt">2. At the command prompt type vmware –v and press Enter.</div>
To view the current build number of the host agent component:
<div class="MsoNormal" style="margin: 0pt">1. Log into the ESX Server host through the VI Client.</div><div class="MsoNormal" style="margin: 0pt">2. Choose Help > About.</div>
And are you looking at the version from the cluster, or directly on the ESX host with VI? Sometimes there is a difference. The service console is the most accurate for the build numbers.