if you're all signed up as a iPhone developer, and you have all your certificates and profiles set, but you're still getting the following error when trying to debug your app on an iPhone/Touch:

Your mobile device has encountered an unexpected error (0xE8000001) during the install phase: Verifying application

check the following:

• in your Info.plist , make sure the Bundle identifier field is set to your AppID (minus the Apple prefix hash), ie: com.yourcompany.${PRODUCT_NAME:identifier}
• in the project settings, make sure the Code Signing Identity field is set to your registered developer name, with the "iPhone Developer " prefix, ie: iPhone Developer: My Name. this must exactly match the name you used when you created your Certificate. once you do that, you will then be able to select the appropriate Profile (dev or publishing) for the Code Signing Provisioning Profile field.

good luck.