--- a/libpjproject.pc.in
+++ b/libpjproject.pc.in
@@ -2,8 +2,8 @@
 
 prefix=@PREFIX@
 exec_prefix=${prefix}
-libdir=@LIBDIR@
-includedir=@INCLUDEDIR@
+libdir=${exec_prefix}/lib
+includedir=${prefix}/include
 
 Name: libpjproject
 Description: Multimedia communication library
--- a/build.mak.in
+++ b/build.mak.in
@@ -314,8 +314,7 @@ export PJ_LIBXX_FILES := $(APP_LIBXX_FIL
 # And here are the variables to use if application is using the
 # library from the install location (i.e. --prefix)
 export PJ_INSTALL_DIR := @prefix@
-export PJ_INSTALL_INC_DIR := @includedir@
 export PJ_INSTALL_LIB_DIR := @libdir@
-export PJ_INSTALL_CFLAGS := -I$(PJ_INSTALL_INC_DIR) -DPJ_AUTOCONF=1 @CFLAGS@
+export PJ_INSTALL_CFLAGS := -DPJ_AUTOCONF=1 @CFLAGS@
 export PJ_INSTALL_CXXFLAGS := @CXXFLAGS@ $(PJ_INSTALL_CFLAGS)
 export PJ_INSTALL_LDFLAGS := -L$(PJ_INSTALL_LIB_DIR) $(APP_LDLIBS)