I spoke to SC, but they don't do warranty claim on saturday, so have to visit them again on a normal day. damn... no free time to do unless wait until school holiday.

But the SC told me it is basically because during production, the glue at the hose to the tank not yet dry completely and they continue on with the rest of the production. So when you fill full tank, then some / little bit of the petrol can back flow and go into cabin.

Indeed, today I didn't fill full tank, so the petrol doesn't touches the hose connecting the tank, and therefore no more fumes inside cabin.

This is what sort of workmanship? Did I took hefty loan to pay someone to ensure the glue didn't dry?

bro, not true....my alza bought OCT 2012 has petrol fumes problem..I don't think perodua solved the problem...is the way they make the car has some technical problems which can cause the petrol fumes in the cabin......why I said this? because even I have changed the new petrol tank and they redo all the parts, the cabin still can smell the fumes....so, is the car technical problem.....

just rectify my problem this morning at subang jaya branch.
it not the leakage problem, some sort of glue or seal on the inner side of the plate between body & fuel cap.
wil notify your for next filling.
hope it solve my problem.