Test cases from Cowlishaw, v2.57. All are pased cleanly.
diff --git a/Lib/test/decimaltestdata/decQuad.decTest b/Lib/test/decimaltestdata/decQuad.decTest
index 4d10069..e9ec663 100644
--- a/Lib/test/decimaltestdata/decQuad.decTest
+++ b/Lib/test/decimaltestdata/decQuad.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.56
+version: 2.57
 
 -- decQuad tests
 dectest: dqAbs