diff --git a/guile-readline/configure.in b/guile-readline/configure.in
index 648df4638..9dc7737f0 100644
--- a/guile-readline/configure.in
+++ b/guile-readline/configure.in
@@ -110,7 +110,7 @@ AC_SUBST(LIBGUILEREADLINE_INTERFACE_CURRENT)
 AC_SUBST(LIBGUILEREADLINE_INTERFACE_REVISION)
 AC_SUBST(LIBGUILEREADLINE_INTERFACE_AGE)
 AC_SUBST(LIBGUILEREADLINE_INTERFACE)
-AC_SUBST(LIBGUILEREADLINE_LTHACK)
+AC_SUBST(LIBGUILEREADLINE_MAJOR)
 
 AC_CONFIG_FILES(Makefile)
 AC_OUTPUT