Cannot test on more than one iPhone

I have a iPhone 4 and a iPhone 3GS. Have managed to download a开发者_StackOverflow中文版nd install the necessary certificates on my iPhone 3GS and set up the phone as a test machine with a sample program. But I cannot do the same with my iPhone 4. I wonder if Apple has placed a limitation that only one iPhone can be registered as test machine.

Hope that some knowledgable person can confirm to me that there is indeed a one test phone limitation. Or somebody can show me how to use both phone models (4 & 3GS) (not at the same time) as test machines.

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If you registered the UDID of a device in the provisioning portal and selected it when you created the mobileprovision, then you should be able to install that provision on the device using Xcode's Organizer. If it doesn't let you, go back to the portal and check the UDIDs you used.

If you can install the profile on your iPhone 4, but the app won't run, check which profile you used for the exact current type of Build of the current Target which you are trying to run (as every Build can use a different profile. And Target settings over-ride Project settings).