diff --git a/php/config/Make.rules b/php/config/Make.rules
index 02aa552..a856448 100644
--- a/php/config/Make.rules
+++ b/php/config/Make.rules
@@ -94,7 +94,8 @@ else
 endif
 
 libdir			= $(top_srcdir)/lib
-install_libdir		= $(prefix)/$(libsubdir)
+install_phplibdir	= $(prefix)/$(libsubdir)
+install_libdir		= $(install_phplibdir)
 
 #
 # Platform specific definitions