iPhoto version 4 wont open pictures burned on CD using version 5?

i have a G5 iSight PowerPC and my girlfriend a G4 ibook (2004). I downloaded our vacation pics from my camera to my G5 using iPhoto v5.0.4 and accidentally erased my camera's memory card after the download. So - I thought I'd burn a disc with the new photos and then import them onto her G4 (which uses iPhoto v 4.0.3). Everytime I insert the photo disc into the G4 I get a message saying iPhoto cannot open album as it was created using a later version of iPhoto.

I'm stuck since she cannot get our vacation pics onto her computer ! Can anyone help? Thanks in advance..

iMac G5 iSight Mac OS X (10.4.7) compatibility, versions, iPhoto v4 , v5

ibook G4 Mac OS X (10.3.9)