KevinG wrote this on the VMWare Knowledgebase

——————————————————————————————–

Run the following command line option with the VM powered off.

vmware-vdiskmanager -r source.vmdk -t 0 dest.vmdk

Remove the original virtual disk using the hardware wizard and add the new virtual disk using the hardware wizard.

The shrink option will now be available for a growable disk.