Warning in xcode 4.0.1 about inability to link a static ios framework

i have upgraded my xcode to 4.0.1 in that i am tring to run my old project which built on xcode 3 but am getting following warning can any one tell me how to fix that

ld: warning: directory not found for option '-F/Developer/new xcode/Platf开发者_运维百科orms/iPhoneOS.platform/Developer/SDKs/iPhoneOS3.1.2.sdk/System/Library/PrivateFrameworks'

You may need to update your linked frameworks.

Go into your project's build phases, and relink the frameworks...

EDIT

Also check the frameworks search path setting, in your project's build settings.