diff --git a/ChangeLog b/ChangeLog
index 044de28..ceee071 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2002-02-28  Havoc Pennington  <hp@redhat.com>
+
+	* pkg-config.1: add a note about the need for AC_SUBST with
+	PKG_CHECK_MODULES. Stefan Kost pointed this out.
+
 2002-02-28  Havoc Pennington  <hp@redhat.com>
 
         Fix for static linking, -l flag order for libs in multiple prefixes
diff --git a/pkg-config.1 b/pkg-config.1
index 4134521..29f3b6c 100644
--- a/pkg-config.1
+++ b/pkg-config.1
@@ -265,6 +265,12 @@ error messages if you specify your own ACTION-IF-NOT-FOUND.
 However, it will set the variable MYSTUFF_PKG_ERRORS, which you can 
 use to display what went wrong.
 
+If you want to use MYSTUFF_LIBS and MYSTUFF_CFLAGS as Makefile.am
+variables (i.e. $(MYSTUFF_LIBS)) then you have to add
+AC_SUBST(MYSTUFF_LIBS) to your configure.in so automake can find the
+variable. You don't need to do this if you use the @MYSTUFF_LIBS@
+syntax in your Makefile.am instead of $(MYSTUFF_LIBS).
+
 .SH METADATA FILE SYNTAX
 To add a library to the set of packages \fIpkg-config\fP knows about,
 simply install a \fI.pc\fP file. You should install this file to