Currently Cacl writes two bytes for the value field when the record type is EXC_BOOLERR_BOOL.  Correct behaviour occurs when the record type is EXC_BOOLERR_ERROR - the value is written as a single byte (since mnErrCode is sal_uInt8)

Excel seems to handle this OK but POI (until the recent patch) does not.

This should be a one line fix to xetable.cxx:
http://svn.services.openoffice.org/ooo/trunk/sc/source/filter/excel/xetable.cxx

Index: xetable.cxx
===================================================================
--- xetable.cxx (revision 268869)
+++ xetable.cxx (working copy)
@@ -648,7 +648,7 @@

 void XclExpBooleanCell::WriteContents( XclExpStream& rStrm )
 {
-    rStrm << sal_uInt16( mbValue ? 1 : 0 ) << EXC_BOOLERR_BOOL;
+    rStrm << sal_uInt8( mbValue ? 1 : 0 ) << EXC_BOOLERR_BOOL;
 }

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