As usual I feel like a complete idiot now that I know what the problem was. I should probably be keeping it simpler while I am learning Yii but I set up my installation according to this cookbook article Organize directories for applications with front-end and back-end. Anyway to make a long story short, I had two model directories /protected/models/ and /protected/backend/models/ I had two WebPage.php files one in each models directory. I seems Yii was reading the /protected/models/ version while I was changing the /protected/backend/models/ version.
Not too smart I did however learn a lot through my investigations, thanks for your help spyros.