Provide support for automake 1.6.3 as included in XCode 3.4.1 on MacOS 10.4, which uses AM_CPPFLAGS where automake 1.10 uses libftgl_la_CPPFLAGS. Patch courtesy of Bzflag's developer bullet_catcher for SF bug 2117545.
diff --git a/src/Makefile.am b/src/Makefile.am
index b0c0430..941b0cd 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -35,6 +35,11 @@ libftgl_la_LDFLAGS = \
libftgl_la_LIBADD = \
$(FT2_LIBS) $(GL_LIBS)
+# automake 1.6.3, as included in XCode 3.4.1 on MacOS 10.4, uses
+# AM_CPPFLAGS where newer automake versions use libftgl_la_CPPFLAGS.
+# Setting AM_CPPFLAGS this way is a no-op for automake 1.10.
+AM_CPPFLAGS = $(libftgl_la_CPPFLAGS)
+
ftgldir = $(includedir)/FTGL
ftgl_HEADERS = $(ftgl_headers)