more os x 10.4
diff --git a/src/cmd/auxstats/Darwin.c b/src/cmd/auxstats/Darwin.c
index 8905edc..168d866 100644
--- a/src/cmd/auxstats/Darwin.c
+++ b/src/cmd/auxstats/Darwin.c
@@ -410,9 +410,11 @@
 {
 	if(first)
 		return;
-	
+
+#ifdef VM_SWAPUSAGE
 	if(sample.xsu_valid)
 		Bprint(&bout, "swap %lld %lld\n", 
 			(vlong)sample.xsu.xsu_used, 
 			(vlong)sample.xsu.xsu_total);
+#endif
 }