All of you have been so helpful to me here over the years that I have been learning Excel and VBA. I finally feel like I can give something back to the community.
Attached is a Non-ActiveX, Non MSCOMCT2.OCX dependent date picker calendar control for VBA userforms. To incorporate it into your project, you would need to copy the clsCalendar class module, and also add all the calendar control objects inside the FrameCalendar frame on the userform (including the frame itself) onto your form. You would also need another control on the form somewhere to be bound to the class, which would receive the user's selected date. Mine is called "TextBoxDate" and it is set in the UserForm code like this:
Anyway, I hope it works for you, or at least it can give you ideas. I hope it's appropriate but I'm sharing this under terms of the "New BSD license," which is really flexible. I don't really mind what you do as long as no one takes this and sells it and pretends they came up with it.
I developed this in 64-bit Excel 2010 beta, on 64-bit Windows 7.