diff --git a/tmac/an-old.tmac b/tmac/an-old.tmac
index 971d2cd5..0251ff41 100644
--- a/tmac/an-old.tmac
+++ b/tmac/an-old.tmac
@@ -134,6 +134,13 @@
 .  nr an-saved-prevailing-indent1 \\n[IN]
 ..
 .
+.nr do-fullcaps-section-heading 1
+.
+.de possibly-fullcaps-transform
+.ie \\$1 .tr aAbBcCdDeEfFgGhHiIjJkKlLmMnNoOpPqQrRsStTuUvVwWxXyYzZ
+.el      .tr aabbccddeeffgghhiijjkkllmmnnooppqqrrssttuuvvwwxxyyzz
+..
+.
 .ds an-extra1
 .ds an-extra2
 .ds an-extra3
@@ -361,7 +368,9 @@
 .  ps \\n[PS-SH]u
 .  ft \\*[HF]
 .  ne (2v + 1u)
+.  possibly-fullcaps-transform \\n[do-fullcaps-section-heading]
 .  if \\n[.$] \&\\$*
+.  possibly-fullcaps-transform 0
 ..
 .
 .de1 SS