diff --git a/acinclude.m4 b/acinclude.m4
index b5e2bae2f..c40fd2a4a 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -268,6 +268,7 @@ if $PKG_CONFIG --exists "$2" ; then
 	AC_MSG_RESULT(yes)
 	$1_CFLAGS=$($PKG_CONFIG --cflags "$2")
 	$1_LIBS=$($PKG_CONFIG --libs "$2")
+	$1_EXISTS=yes
 else
 	AC_MSG_RESULT(no)
 fi
@@ -278,7 +279,7 @@ AC_SUBST($1_LIBS)
 
 AC_DEFUN([TUXBOX_APPS_LIB_PKGCONFIG],[
 _TUXBOX_APPS_LIB_PKGCONFIG($1,$2)
-if test -z "$$1_CFLAGS" && test -z "$$1_LIBS"; then
+if test x"$$1_EXISTS" != xyes; then
 	AC_MSG_ERROR([could not find package $2]);
 fi
 ])
diff --git a/configure.ac b/configure.ac
index 057e98ba0..9f538a33b 100644
--- a/configure.ac
+++ b/configure.ac
@@ -46,11 +46,11 @@ TUXBOX_APPS_LIB_CONFIG(CURL,curl-config)
 TUXBOX_APPS_LIB_CONFIG(FREETYPE,freetype-config)
 # TUXBOX_APPS_LIB_PKGCONFIG(OPENSSL,openssl)
 TUXBOX_APPS_LIB_PKGCONFIG_CHECK(ID3TAG,libid3tag)
-if test -z "$ID3TAG_CFLAGS" ; then
+if test x"$ID3TAG_EXISTS" != xyes; then
 	TUXBOX_APPS_LIB_PKGCONFIG(ID3TAG,id3tag)
 fi
 TUXBOX_APPS_LIB_PKGCONFIG_CHECK(MAD,libmad)
-if test -z "$MAD_CFLAGS" ; then
+if test x"$MAD_EXISTS" != xyes; then
 	TUXBOX_APPS_LIB_PKGCONFIG(MAD,mad)
 fi
 TUXBOX_APPS_LIB_PKGCONFIG(PNG,libpng)