I've got may old pictures on my device without EXIF Data. (most from a Nokia 6230i and other ones)

I want to manage and order them with the others in my N900. But when I edit the Tag, the File date changes or the Images itself ordered not in the correct sequence when I try to order them by Date.

At the moment the File Date is for me the Date when the Picture was taken.

Is there a way to write the File Date to the JPEG EXIF when there are no "EXIF Picture Create Date" Data in the File?

Edit: I've got only a N900 with Maemo, a N95 with Symbian and Windows XP.