How can I create acknowledgements for unacknowledged contributions

Hello, 

I recently did some gift entry for our new fiscal year, but did't realize that I didn't have acknowledgement rules set up yet for a particular campaign, and so there are a number of contributions now that did not have acknowledgements created for it. Is there a way to go back and create acknowledgements for these contributions without having to reenter everything now that I have rules set up for that campaign? Can I "retroactively" acknowledge certain contributions? Thanks!

David