diff --git a/acinclude.m4.in b/acinclude.m4.in
index b41ecaf..4a2ccfe 100644
--- a/acinclude.m4.in
+++ b/acinclude.m4.in
@@ -3571,8 +3571,6 @@ AC_DEFUN([AC_CHECK_SOCKLEN_T],
    fi
    AC_DEFINE_UNQUOTED(kde_socklen_t, $kde_cv_socklen_t_equiv,
                      [type to use in place of socklen_t if not defined])
-   AC_DEFINE_UNQUOTED(ksize_t, $kde_cv_socklen_t_equiv,
-                     [type to use in place of socklen_t if not defined (deprecated, use kde_socklen_t)])
 ])
 
 dnl This is a merge of some macros out of the gettext aclocal.m4