Error while importing the framework

My app deals with phone call.So I added coretelephony framework to my proje开发者_Python百科ct.But when I try to import the framework to my appdelegate,I get the error "No such file directory" Can any one find the solution for that.I use xcode 4.0.1

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HI after you add core telephony framework then add

#import <CoreTelephony/CoreTelephonyDefines.h> to your appDelegate.h file

It will solve your problem.