Using \namespace In My Yii Application

I have two apps: "frontend" and "backend" as described in wiki. Sometime in "frontend" and "backend" I refer to same models, even if in "backend" I have to add some methods to make it work under administration.

For example "modelA" in frontend has methodA and methodB, but now I want to create another "modelA" -this time in backend- extending the one in frontend, adding methodC, methodD and methodX.

I could easily do that with Yii:import(‘frontend.modelA’) and create a class BackendModelA exentds ModelA but I’m would like to know if it is possible to that using PHP namespace, and I’m very new to that.

In this comment: it seems it’s possible but it’s not very clear to me how to implement.

Any hint? TIA