i am using SDK 3.0 and iPhone 3.0 (upgraded from 2.2.1). when i try to install on my iPhone device, i got an error like "disk image can not be mounted " and also i am getting same error on organizer window of xcode.
i am not able to deploy my app developed using SDK 3.0 on iPhone
The first thing I'd check in this case are the build versions between the SDK and your iPhone.
If you're developing against the pre-release SDK, but installed 3.0 on the phone via iTunes, your build versions are probably different. Might need to download the latest SDK from the iPhone Dev Center.