iTunes App Store Review Process...FAIL!

Thank you for submitting iGBMobile to the App Store.

We’ve completed the review of your app, however, we cannot post this version to the App Store because it is using a private API, which is not in compliance with the App Store Review Guidelines :

2.5 Apps that use non-public APIs will be rejected

We have included additional details below to help explain the issue and hope you'll consider revising and resubmitting your application.

The non-public API that is included in your application is unable to parse xml text. If you have defined a method in your source code with the same name as this API, we suggest altering your method name so that it no longer collides with Apple's private API to avoid your application being flagged in future submissions.

This is an excerpt of a app store rejection email I received from Apple in reference to my submission of version 1.33 of iGigBook Mobile(iGBMobile). I have bolded the non-public API that I'm alleged to be using, which is:

unable to parse xml text

The API is so private, they can't even included its name in the email.