See attached document. The overflow is on page 1 but FOP reports page 5. Here is the FOP output: Content overflows the viewport of the fo:region-body on page 5 in block-progression direction by 5000 millipoints. (See position 23:80) This has the side effect that the third page is numbered 5 instead of 3.
Created attachment 29199 [details] FO file illustrating the issue
Created attachment 29200 [details] Resulting PDF output
Fixed in rev. 1371386: http://svn.apache.org/viewvc?rev=1371386&view=rev