Hiding a sheet in Excel 2007 (with a password) OR hide VBA code in Excel

I found a way to hide Excel sheets which is as follows: set the visibility of the sheet to VeryHidden in the VBAProject properties and then password protect VBAProject properties.

This is great, but in Excel 2007, if you save it as XLSX, the VBAProject password protection is stripped and you can view the VBA code. Is there any way to prevent this?

OR, is there any other way to hide an Excel 2007 sheet?

Here is what you do in Excel 2003:

1. In your sheet of interest, go to Format -> Sheet -> Hide and hide your sheet.
2. Go to Tools -> Protection -> Protect Workbook, make sure Structure is selected, and enter your password of choice.

Here is what you do in Excel 2007:

1. In your sheet of interest, go to Home ribbon -> Format -> Hide & Unhide -> Hide Sheet and hide your sheet.
2. Go to Review ribbon -> Protect Workbook, make sure Structure is selected, and enter your password of choice.

Once this is done, the sheet is hidden and cannot be unhidden without the password. Make sense?

If you really need to keep some calculations secret, try this: use Access (or another Excel workbook or some other DB of your choice) to calculate what you need calculated, and export only the "unclassified" results to your Excel workbook.