Solution : https://service.sap.com/sap/support/notes/500363 (SAP Service marketplace login required)
Key words : 
4 etw000    existing field  imported field4 etw000      keypart, corrected r3trans versions display march 04, sap service marketplace software center, 'b'  'x'4 etw000      len, sap service marketplace, data file exported, internal r3trans change, ' '  ' '4 etw000      format, r3trans patch, relevant r3trans
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