  We show that a standard calculation of the splitting function for the
nonsinglet structure function h_1 does not lead to the expected result. The
calculation is compared to the corresponding derivation of the splitting
function for the nonsinglet polarized structure function g_1. We analyze
possible explanations for the unexpected result and discuss its implications.
PACS: 11.10.Hi; 11.40.-q; 11.55.Ds; 13.88.+e
