ContactsContract.Contacts issue

Hi

I am upgrading my contactbook application from 1.6 to 2.0. To retrive the contacts i am using followin code :

Cursor mCursor = getContentResolver().query(ContactsContract.Contacts.CONTENT_URI ,null,null,null,null);
int nameFieldColumnIndex = mCursor.getColumnIndex(PhoneLookup.DISPLAY_NAME); ​

String contact = mCursor.getString(nameFieldColumnIndex);

But it is giving me this exception
12-04 10:50:05.811: ERROR/AndroidRuntime(582): java.lang.RuntimeException: Unable to start activity ComponentInfo{lgsi.app.pkg/lgsi.app.pkg.ContactActivity}: android.database.CursorIndexOutOfBoundsException: Index -1 requested, with a size of 3

Plz provide some guidelines..
Thanks,
Sourabh