I had the same issue with my iPhone 3G and with my iPod touch 1st gen. I returned both devices to an Apple premium reseller. The salesman said that Apple might not cover the repair and that I might have to pay for gegrint my devices fixed. But I said he just needed to send it to Apple. A few weeks later I received a brand new iPod touch and a brand new iPhone 3G. Now, About 3 months later, there is again dust under the screen of my iPhone... I think I'll just open my phone with a screwdriver and remove it myself. Apple seems to have a problem with keeping their products dust-free. I recently bought an iMac and there was a lot of dust behnd the screen.. But the iMac screen is easier to clean.