VMDK not included in the OVA

Here is the situation.

We have a VM which has two disks (VMDK) bundled in a OVA.

The first disk is where all the software is installed. The second disk is the data disk.

The software initializes the second disk after boot.

The second disk is not required to boot the VM.

Is there a way I can describe in the OVF  the size of the second disk required but not include the VMDK.

During installation of the VM the VMDK file of appropriate size could be provided by the ESXi hypervisor.

Any pointers for such configuration would be helpful.

Thanks