Can you rename the result set parameter to, say, "ScoreResultSet"?
So
declareParameter(new SqlReturnResultSet("ScoreResultSet", mScoreMapper));
and
List<Score> lAllScore = ((List<Score>)lAllScoreResult.get("ScoreResultSet"));
The name you are currently using also gets used by spring when it auto generates names for result sets.
I think you may therefore now be returning a different, unprocessed, result set than the mapped one from the SqlReturnResultSet parameter you declared.
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EDIT:
I just found this other question of yours: Java StoredProcedure with SqlReturnResultSet not working and assuming that we are talking about the same stored procedure:
I suspect you have two selects in the stored procedure and it returns two result sets. You should declare two (properly named) SqlReturnResultSet parameters instead of one. The order of the declaration matters, so you cannot declare just one and give it the name usually assigned to the second one.