Today I have made 2 scripts which ease ESX 3.5 patch management for me.
First script (getpatch) is to download all needed patches onto a local server and extract them. The second (patchesx) is run on the ESX server to install the patches.
In getpatch you need to set the PATCHDIR to the proper location. In patchesx you need to set the DEPOT-path according to your webserver.