Shark was unable to find symbol information for this address range - iPhone

I'm trying to use Shark to determine which method(s) are taking the most time in my iPhone app. After sampling, I get this: alt text http://img69.imageshack.us/img69/7871/screenshot20091117at503.png

Clicking the "!" button yields:

Shark was unable to find symbol information for this address range. Typically this happens because the application was compiled without sy开发者_如何学Cmbols or they have been subsequently stripped away. In Xcode, make sure the "Generate Debug Symbols" checkbox is selected (passes the -g flag to the compiler). Note that this does not affect code optimization, and does not typically alter performance significantly. However, the extra symbol information does consume significantly more space and may bloat the size of the executable.

But I AM using the Debug option, and I am running on my Device. And Generate Debug Symbols IS checked. So what's wrong?

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Don't know if this applies to Shark on device, but I know that when running Instruments with the iPhone Simulator, one has to select the most recent SDK. If you run with a previous SDK, you see no debug info.