The company must know how much tax it will be paying, so just...

The company must know how much tax it will be paying, so just cancel the idea of a capital return and declare the franked dividend.

Then determine how much tax will be paid in the instalments in this financial year for the 2012 year, so they can determine the franking account balance, and pay that amount out as a second franked dividend later in the year. That should compensate the loss of the capital return.

After all, we did not invest in the company for a capital return. We invested because of the assets of the company, the quality of the management, and the expectations of a profit being derived from the development/sale of the assets.