diff --git a/cf/krb-func-getlogin.m4 b/cf/krb-func-getlogin.m4
new file mode 100644
index 000000000..a0a173fcf
--- /dev/null
+++ b/cf/krb-func-getlogin.m4
@@ -0,0 +1,22 @@
+dnl
+dnl $Id$
+dnl
+dnl test for POSIX (broken) getlogin
+dnl
+
+
+AC_DEFUN(AC_FUNC_GETLOGIN, [
+AC_CHECK_FUNCS(getlogin setlogin)
+if test "$ac_cv_func_getlogin" = yes; then
+AC_CACHE_CHECK(if getlogin is posix, ac_cv_func_getlogin_posix, [
+if test "$ac_cv_func_getlogin" = yes -a "$ac_cv_func_setlogin" = yes; then
+	ac_cv_func_getlogin_posix=no
+else
+	ac_cv_func_getlogin_posix=yes
+fi
+])
+if test "$ac_cv_func_getlogin_posix" = yes; then
+	AC_DEFINE(POSIX_GETLOGIN, 1, [Define if getlogin has POSIX flavour (and not BSD).])
+fi
+fi
+])