diff -ur lavaps-2.4.orig/change_tracking.hh lavaps-2.4/change_tracking.hh
--- lavaps-2.4.orig/change_tracking.hh	2003-07-15 00:42:06.000000000 -0400
+++ lavaps-2.4/change_tracking.hh	2004-07-09 23:54:47.820363344 -0400
@@ -76,11 +76,11 @@
 class sum_change_tracking : public change_tracking<T> {
 protected:
 	static SUM s_;
-	void update_sum() { s_.sum_ += change_; }
+	void update_sum() { s_.sum_ += change_tracking<T>::change_; }
 public:
 	sum_change_tracking() {};
-	sum_change_tracking(T first) : change_tracking<T>(first) { update_sum(frst); };
-	~sum_change_tracking() { tick_incr(-last_); };
+	sum_change_tracking(T first) : change_tracking<T>(first) { update_sum(first); };
+	~sum_change_tracking() { tick_incr(-change_tracking<T>::last_); };
 
 
 	void tick_set(T current) { change_tracking<T>::tick_set(current); update_sum(); };