If that's the reason they're giving then surely we should be able to get our phones debranded/have htc's generic firmware applied?
Do HTC have service centres/approved engineers? It would be good to get the go ahead to have them replace the firmware, if everyone can agree that there's a problem (demonstrably there is) then who could argue against doing that?
EDIT: Just checked their website, Malaysia seems to be your best bet for an HTC service centre. If you're in the area, why not pop in... hoho.