diff --git a/configure.ac b/configure.ac
index bf4e9b9..c6f5100 100644
--- a/configure.ac
+++ b/configure.ac
@@ -10,13 +10,16 @@ AC_PROG_CC_C99
 
 # Checks for libraries.
 PKG_CHECK_MODULES([gammu], [gammu >= 1.0])
+PKG_CHECK_MODULES([libconfuse], [libconfuse >= 2.0])
 
 # Checks for header files.
 AC_CHECK_HEADERS([fcntl.h signal.h stdlib.h string.h syslog.h unistd.h])
 
 # Checks for typedefs, structures, and compiler characteristics.
+AC_TYPE_PID_T
 
 # Checks for library functions.
+AC_FUNC_FORK
 
 AC_CONFIG_FILES([Makefile])
 AC_OUTPUT
diff --git a/yasnd.c b/yasnd.c
index aff8f8a..679f098 100644
--- a/yasnd.c
+++ b/yasnd.c
@@ -9,6 +9,7 @@
 #include <syslog.h>
 #include <signal.h>
 #include <string.h>
+#include <confuse.h>
 // #include <gammu/gammu.h>
 
 // Target hosts count