Here is a patch to the headers and footers that does the extraction of the headers an footers of existing sheets. Solves the problem when a person retrieves the header repeatedly to update it.
Created attachment 1860 [details] [PATCH] HSSFHeader and HSSFFooter
done, please crosscheck.
I checked and it didn't look like the patch had been applied.
Well if its not applied now I dunno what to tell you.. I must goofed. Try again please.
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