Here's how it's done:
Download the "HP Management Agents for VMware ESX 4.x" here and the "HP Array Configuration Utility for Linux" here.
Using the vSphere client utility to copy the files to the server preferably in a new folder.
Now, SSH into the server and CD into the directory where the new files are and extract the .tgz file by run the following:
tar -zxvf hpmgmt-8.3.0-vmware4x.tgz
now run the shell script using the --install switch:
./hpmgmt/830/install830vibs.sh --install
install the ACU by running:
rpm -i cpqacuxe-8.35-7.0.noarch.rpm
enable remote ACU control:
cpqacuxe -R
And that's it.
Now you should be able to access the HPSIM homepage by browsing to
https://yourserver
logging in with your vSphere root credentials, and now you should have a link to ACU at the homepage.
UPDATE:
The correct URL for the HP System Management page is:
https://yourserver:2381