Hi all - got a problem with my iphone 3gs. Sometimes (maybe one in 20) when i get a text or a calender alert the phone will light up (as always) but then the screen stays lit up until I ok it. Now this is fine if im using the phone or aware of this - but othertimes i'll go to my phone, and it's clearly been on for the past four hours - it's hot, and the battery has seriously drained. Common problem? Solution? Back to apple? Thanks for any advice!