Unfortunately, it's impossible: http://www.commentcamarche.net/faq/sujet 3186 myths about getting a sharp image from a blurry photo (unless maybe in NCIS or CSI).
Anonymous user
Even if the blurs are minimal?
Lazarey
If there are really a few, it might be possible with filters to remove the noise or enhance the contours. I'm not exactly sure.
Anonymous user
Thanks for your advice.
Madrigan
Paint.NET (free software) has an effect that improves sharpness and works quite well, but it all depends on the originals... There's no magic software :) (in Paint.NET: Effects, Photo, Enhance Sharpness)