unstable openoffice metadata

[bill lam <cbill lam gmail com>]

I found that if a workbook has been saved from openoffice. It add some
metadata into it and gnumeric retains this metadata even if the
workbook was converted into gnumeric's xml format.  However the 
metadata changes from version to version of gnumeric even nothing
actually changed and that workbook was not accessed by openoffice
again.  As an example, the diff of a workbook 

@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <gnm:Workbook xmlns:gnm="http://www.gnumeric.org/v10.dtd"; 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"; xsi:schemaLocation="http://www.gnumeric.org/v9.xsd";>
-  <gnm:Version Epoch="1" Major="9" Minor="15" Full="1.9.15"/>
+  <gnm:Version Epoch="1" Major="9" Minor="16" Full="1.9.16"/>
   <gnm:Attributes>
     <gnm:Attribute>
       <gnm:type>4</gnm:type>
@@ -30,12 +30,12 @@
   </gnm:Attributes>
   <office:document-meta xmlns:office="urn:oasis:names:tc:opendocument:xmlns:office:1.0" 
xmlns:xlink="http://www.w3.org/1999/xlink"; xmlns:dc="http://purl.org/dc/elements/1.1/"; 
xmlns:meta="urn:oasis:names:tc:opendocument:xmlns:meta:1.0" xmlns:ooo="http://openoffice.org/2004/office"; 
office:version="1.1">
     <office:meta>
-      <meta:creation-date>2009-04-22T19:24:48Z</meta:creation-date>
+      <meta:user-defined meta:name="msole:codepage" meta:type="string">-535</meta:user-defined>
       <meta:user-defined meta:name="gsf:thumbnail" meta:type="string"></meta:user-defined>
       <meta:editing-cycles>0</meta:editing-cycles>
-      <dc:date>2009-04-22T19:24:48Z</dc:date>
-      <meta:user-defined meta:name="msole:codepage" meta:type="string">-535</meta:user-defined>
       <meta:editing-duration>2009-04-22T19:24:48Z</meta:editing-duration>
+      <meta:creation-date>2009-04-22T19:24:48Z</meta:creation-date>
+      <dc:date>2009-04-22T19:24:48Z</dc:date>
       <meta:print-date>2009-04-22T19:24:48Z</meta:print-date>
     </office:meta>
   </office:document-meta>

specifically the position for the lines of creation-date and codepage
oscillating for nearly every release of gnumeric.  Is this related to
gnumeric itself or other xml library?  Is there any option in
ssconvert to strip off all foreign metadata for gnumeric xml target?

-- 
regards,
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