diff -up ./configure.ac.use-system-rply ./configure.ac
--- ./configure.ac.use-system-rply	2011-09-12 19:21:48.000000000 +0300
+++ ./configure.ac	2011-09-22 19:58:01.261676420 +0300
@@ -78,6 +78,20 @@ AS_IF([test "x$have_mx" = "xno"],
 
 AM_CONDITIONAL([HAVE_MX], [test "x$have_mx" = "xyes"])
 
+dnl Prefer the system version of rply if available
+AC_CHECK_HEADER([rply/rply.h], [have_rply=yes], [have_rply=no])
+
+if test x$have_rply = "xno"; then
+        AC_MSG_NOTICE([rply was not found. Using internal copy])
+else
+        RPLY_CFLAGS=""
+        RPLY_LIBS="-lrply"
+        AC_SUBST(RPLY_CFLAGS)
+        AC_SUBST(RPLY_LIBS)
+fi
+
+AM_CONDITIONAL([USE_INTERNAL_RPLY], [test "x$have_rply" = "xno"])
+
 # prefixes for fixing gtk-doc references
 CLUTTER_PREFIX="`$PKG_CONFIG --variable=prefix clutter-1.0`"
 AC_SUBST(CLUTTER_PREFIX)
diff -up ./mash/Makefile.am.use-system-rply ./mash/Makefile.am
--- ./mash/Makefile.am.use-system-rply	2011-09-12 19:08:11.000000000 +0300
+++ ./mash/Makefile.am	2011-09-22 20:00:03.136152776 +0300
@@ -1,4 +1,6 @@
+if USE_INTERNAL_RPLY
 SUBDIRS = rply
+endif
 
 lib_LTLIBRARIES = libmash-@MASH_API_VERSION@.la
 
@@ -7,6 +9,7 @@ INCLUDES = \
 
 AM_CPPFLAGS = \
 	-DMASH_COMPILATION=1 \
+	@RPLY_CFLAGS@ \
 	@CLUTTER_CFLAGS@
 
 enum_h = \
@@ -68,8 +71,15 @@ libmash_@MASH_API_VERSION@_la_LDFLAGS =
 	-version-info "@MASH_LT_CURRENT@:@MASH_LT_REVISION@:@MASH_LT_AGE@"
 
 libmash_@MASH_API_VERSION@_la_LIBADD = \
-	@CLUTTER_LIBS@ \
+	@CLUTTER_LIBS@
+
+if USE_INTERNAL_RPLY
+libmash_@MASH_API_VERSION@_la_LIBADD += \
 	rply/librply.la
+else
+libmash_@MASH_API_VERSION@_la_LIBADD += \
+	@RPLY_LIBS@
+endif
 
 CLEANFILES =