11.5.10 to R12.1.1 upgrade : PO_HEADERS_N10.xdf due to following reason.

Hi,
During upgrade the above xdf fails with following error.   We skipped and continued.   Can you please let me know a fix for this issue.

Thanks


XDF file application started. Current time is: Wed Jul 10 16:41:38 EDT 2013

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Applying XDF file : /u01/app/oracle/apps/apps_st/appl/po/12.0.0/patch/115/xdf/PO_HEADERS_N10.xdf
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Index hashcode(s) extracted from the XDF.

Hashcodes generated for DB indexes.


Index PO_HEADERS_N10 exists under PO schema.
Checking for differences
The PO_HEADERS_N10 on table PO_HEADERS_ALL has wrong Columns or columns in the wrong Order
Index PO_HEADERS_N10 currently in the database