IPhoto - sort images my date photo was taken (metadata)

Question

The Sort by Date Photo functunality in iPHOTO appears to be flawed.
I opened up my photos in Photoshop, and looked at the METADATA for when the photos were taken.
When I sorted them "By Date" in iPHOTO, they looked in an odd order.
Then I figured it out.
They were sorted by the "date" THEY WERE MODIFED IN PHOTOSHOP (the date stamp on the file).
This has nothing to do with the date the photo was taken (in the metadata), which is what most photographers would be interested in.
How do you get iPHOTO to actually sort event photos by the DATE the photo was TAKEN?

Answer 1

Were these photos edtied by PS outside of iPhoto and imported or from within iPhoto with PS as the external editor of choice? Are they jpeg format?
No matter if I edit outside of iPhoto or from withing iPhoto the files are sorted by the EXIF Capture date.  Make a temporary, backup copy (if you don't already have a backup copy) of the library and try the following:
1 - delete the iPhoto preference file, com.apple.iPhoto.plist, that resides in your
     User/Home()/Library/ Preferences folder.
2 - delete iPhoto's cache file, Cache.db, that is located in your
     User/Home()/Library/Caches/com.apple.iPhoto folder. 
3 - launch iPhoto and try again.
NOTE: If you're moved your library from its default location in your Home/Pictures folder you will have to point iPhoto to its new location when you next open iPhoto by holding down the Option key when launching iPhoto.  You'll also have to reset the iPhoto's various preferences.
OT