Camm, it appears that the quadpack code has not changed, so if there's any difference in Maxima, it would have to be outside of quadpack. Maybe the default float type has changed from 64 bits to 80 bits or vice versa? Only a guess; I don't know what else to suggest.
You could narrow the scope by tracing SLATEC::DQK31 and then only calling that function; maybe that helps a little. best, Robert
