diff --git a/configure.ac b/configure.ac
index b6cc7c17..b407c89a 100755
--- a/configure.ac
+++ b/configure.ac
@@ -1,3 +1,5 @@
+m4_pattern_allow([PKG_CHECK_EXISTS])
+
 AC_INIT([rtorrent], [0.9.8], [sundell.software@gmail.com])
 
 AC_CONFIG_HEADERS([config.h])