diff --git a/configure.ac b/configure.ac
index 5446e906..922f7cbc 100644
--- a/configure.ac
+++ b/configure.ac
@@ -350,11 +350,14 @@ AC_HEADER_TIME
 AC_STRUCT_TM
 
 dnl Checks for library functions.
+old_LIBS=$LIBS
+LIBS="$base_LIBS $network_LIBS $opengl_LIBS"
 AC_TYPE_SIGNAL
 AC_FUNC_VPRINTF
-AC_CHECK_FUNCS( \
+AC_CHECK_FUNCS( [ \
         ftime gettimeofday timegm memcpy bcopy mktime strstr rand \
-	random drand48 setitimer getitimer signal GetLocalTime rint getrusage )
+	random drand48 setitimer getitimer signal GetLocalTime rint getrusage ] )
+LIBS=$old_LIBS
 
 AM_CONFIG_HEADER(simgear/simgear_config.h)