iphoto discards creation date information

Todays interesting surprise, after setting up my system and getting ready to edit all my photos in iphoto & export with hazel sorting it into folders again, based on creation date...

Not so! I just couldn't believe it, but truly: iphoto changes the original date of taking the photo, it does keep the exif original creation date, but my poor hazel uses the file creation date, and that becomes the day of exporting from iphoto, a completely useless time for me, as the changes have been made before and it also put the modification date to this, which at least is slightly more correct, although not the time that indicates when i edited the photo

So back to finding out which program to use again, and if i am going to use a new camera the choice is kind of taken already, as only lightroom has raw editing for sigma, how i miss picasa!