diff --git a/checkin_notes b/checkin_notes
index 7ba1ee445f..c9cba96566 100644
--- a/checkin_notes
+++ b/checkin_notes
@@ -4317,3 +4317,15 @@ Charlie 13 June 2012
 
     client/
         coproc_detect.cpp
+
+David  14 June 2012
+    - scheduler: send <dont_use_dcf> only if client is 7.0.28 or later.
+
+    sched/
+        sched_types.cpp
+    vda/
+        ssim.cpp
+        vdad.cpp
+        des.h
+        stats.cpp,h
+        vda_lib.cpp,h
diff --git a/sched/sched_types.cpp b/sched/sched_types.cpp
index 1274ca1a4f..b9fd633bc8 100644
--- a/sched/sched_types.cpp
+++ b/sched/sched_types.cpp
@@ -620,11 +620,12 @@ int SCHEDULER_REPLY::write(FILE* fout, SCHEDULER_REQUEST& sreq) {
     fprintf(fout,
         "Content-type: text/xml\n\n"
         "<scheduler_reply>\n"
-        "<scheduler_version>%d</scheduler_version>\n"
-        //"<dont_use_dcf/>\n"
-        ,
+        "<scheduler_version>%d</scheduler_version>\n",
         BOINC_MAJOR_VERSION*100+BOINC_MINOR_VERSION
     );
+    if (sreq.core_client_version >= 70028) {
+        fprintf(fout, "<dont_use_dcf/>\n");
+    }
     if (strlen(config.master_url)) {
         fprintf(fout,
             "<master_url>%s</master_url>\n",
diff --git a/vda/des.h b/vda/des.h
index b245fe50bc..61373b93ae 100644
--- a/vda/des.h
+++ b/vda/des.h
@@ -18,6 +18,9 @@
 // The world's smallest discrete event simulator.
 // Uses the STL "heap" data structure for efficient event storage.
 
+#ifndef _DES_
+#define _DES_
+
 #include <vector>
 #include <algorithm>
 
@@ -32,7 +35,7 @@ struct EVENT {
     virtual void handle(){}
 };
 
-bool compare(EVENT* e1, EVENT* e2) {
+inline bool compare(EVENT* e1, EVENT* e2) {
     return (e1->t > e2->t);
 }
 
@@ -77,3 +80,7 @@ struct SIMULATOR {
         }
     }
 };
+
+extern SIMULATOR sim;
+
+#endif
diff --git a/vda/ssim.cpp b/vda/ssim.cpp
index 89ebe780f2..d41500afc9 100644
--- a/vda/ssim.cpp
+++ b/vda/ssim.cpp
@@ -38,6 +38,7 @@
 #include <limits.h>
 
 #include "des.h"
+#include "stats.h"
 #include "vda_lib.h"
 
 using std::set;
@@ -119,6 +120,10 @@ char* now_str() {
     return time_str(sim.now);
 }
 
+void show_msg(char* msg) {
+    printf("%s: %s", time_str(sim.now), msg);
+}
+
 struct CHUNK;
 struct CHUNK_ON_HOST;
 struct META_CHUNK;
@@ -204,8 +209,8 @@ struct SIM_FILE : VDA_FILE_AUX, EVENT {
         } else {
             meta_chunk = new META_CHUNK(this, NULL, size, 0, id);
 #ifdef EVENT_DEBUG
-            printf("created file %d: size %f encoded size %f\n",
-                id, size, disk_usage.value
+            printf("created file %d: size %f GB encoded size %f GB\n",
+                id, size/1e9, disk_usage.value/1e9
             );
             t = sim.now + 500.*86400;
             sim.insert(this);
@@ -451,10 +456,12 @@ void CHUNK::download_complete() {
 }
 
 int META_CHUNK::encode() {
+    printf("%s: encoding metachunk %s\n", now_str(), name);
     return 0;
 }
 
 int META_CHUNK::decode() {
+    printf("%s: decoding metachunk %s\n", now_str(), name);
     return 0;
 }
 
diff --git a/vda/stats.cpp b/vda/stats.cpp
index 1178245ada..f162f5befd 100644
--- a/vda/stats.cpp
+++ b/vda/stats.cpp
@@ -19,23 +19,9 @@
 #include <stdio.h>
 #include <limits.h>
 
+#include "vda_lib.h"
 #include "stats.h"
 
-//#define SAMPLE_DEBUG
-
-char* time_str(double t) {
-    static char buf[256];
-    int n = (int)t;
-    int nsec = n % 60;
-    n /= 60;
-    int nmin = n % 60;
-    n /= 60;
-    int nhour = n % 24;
-    n /= 24;
-    sprintf(buf, "%4d days %02d:%02d:%02d", n, nhour, nmin, nsec);
-    return buf;
-}
-
 void STATS_ITEM::init(const char* n, const char* filename, STATS_KIND k) {
     f = fopen(filename, "w");
     strcpy(name, n);
@@ -56,19 +42,23 @@ void STATS_ITEM::init(const char* n, const char* filename, STATS_KIND k) {
 }
 
 void STATS_ITEM::sample(double v, bool collecting_stats, double now) {
-#ifdef SAMPLE_DEBUG
-    switch (kind) {
-    case DISK:
-        printf("%s: %s: %f GB -> %f GB\n", now_str(), name, value/1e9, v/1e9);
-        break;
-    case NETWORK:
-        printf("%s: %s: %f Mbps -> %f Mbps\n", now_str(), name, value/1e6, v/1e6);
-        break;
-    case FAULT_TOLERANCE:
-        printf("%s: %s: %.0f -> %.0f\n", now_str(), name, value, v);
-        break;
+    char buf[256];
+    if (value != v) {
+        switch (kind) {
+        case DISK:
+            sprintf(buf, "%s: %f GB -> %f GB\n", name, value/1e9, v/1e9);
+            show_msg(buf);
+            break;
+        case NETWORK:
+            sprintf(buf, "%s: %f Mbps -> %f Mbps\n", name, value/1e6, v/1e6);
+            show_msg(buf);
+            break;
+        case FAULT_TOLERANCE:
+            sprintf(buf, "%s: %.0f -> %.0f\n", name, value, v);
+            show_msg(buf);
+            break;
+        }
     }
-#endif
     double old_val = value;
     value = v;
     if (!collecting_stats) return;
diff --git a/vda/stats.h b/vda/stats.h
index 5794d8df67..9de8c86619 100644
--- a/vda/stats.h
+++ b/vda/stats.h
@@ -19,6 +19,11 @@
 // (server disk usage, up/download rate, fault tolerance level)
 //
 
+#ifndef _STATS_
+#define _STATS_
+
+#include <stdio.h>
+
 typedef enum {DISK, NETWORK, FAULT_TOLERANCE} STATS_KIND;
 
 struct STATS_ITEM {
@@ -40,4 +45,4 @@ struct STATS_ITEM {
     void print_summary(FILE* f, double now);
 };
 
-extern char* time_str(double);
+#endif
diff --git a/vda/vda_lib.cpp b/vda/vda_lib.cpp
index bf4a092bca..aa7afc46bf 100644
--- a/vda/vda_lib.cpp
+++ b/vda/vda_lib.cpp
@@ -258,10 +258,10 @@ int META_CHUNK::recovery_action(double now) {
         //
         for (i=0; i<j; i++) {
             DATA_UNIT* c = recoverable[i];
-            printf("  Min failures of %s: %d\n", c->name, c->min_failures);
+            //printf("  Min failures of %s: %d\n", c->name, c->min_failures);
             min_failures += c->min_failures;
         }
-        printf("  our min failures: %d\n", min_failures);
+        //printf("  our min failures: %d\n", min_failures);
     }
     return 0;
 }
@@ -277,6 +277,8 @@ bool CHUNK::download_in_progress() {
 
 int CHUNK::recovery_action(double now) {
     int retval;
+    char buf[256];
+
     VDA_FILE_AUX* fp = parent->dfile;
     if (data_now_present) {
         present_on_server = true;
@@ -309,9 +311,8 @@ int CHUNK::recovery_action(double now) {
             present_on_server = false;
             status = RECOVERABLE;
             min_failures = fp->policy.replication;
-#ifdef EVENT_DEBUG
-            printf("%s: %s replicated, removing from server\n", now_str(), name);
-#endif
+            sprintf(buf, "%s replicated, removing from server\n", name);
+            show_msg(buf);
             parent->dfile->disk_usage.sample_inc(
                 -size,
                 fp->collecting_stats(),
@@ -471,3 +472,16 @@ int META_CHUNK::expand() {
     }
     return 0;
 }
+
+char* time_str(double t) {
+    static char buf[256];
+    int n = (int)t;
+    int nsec = n % 60;
+    n /= 60;
+    int nmin = n % 60;
+    n /= 60;
+    int nhour = n % 24;
+    n /= 24;
+    sprintf(buf, "%4d days %02d:%02d:%02d", n, nhour, nmin, nsec);
+    return buf;
+}
diff --git a/vda/vda_lib.h b/vda/vda_lib.h
index 849cbcd868..fe55318370 100644
--- a/vda/vda_lib.h
+++ b/vda/vda_lib.h
@@ -33,6 +33,9 @@
 //
 #define VDA_HOST_TIMEOUT (86400*4)
 
+extern void show_msg(char*);
+extern char* time_str(double);
+
 struct META_CHUNK;
 
 struct VDA_FILE_AUX : VDA_FILE {
diff --git a/vda/vdad.cpp b/vda/vdad.cpp
index c844fe571a..0d36927001 100644
--- a/vda/vdad.cpp
+++ b/vda/vdad.cpp
@@ -42,6 +42,10 @@ using std::set;
 
 #include "vda_lib.h"
 
+void show_msg(char* msg) {
+    printf("%s", msg);
+}
+
 // return the name of a file created by Jerasure's encoder
 //
 // encoder creates files with names of the form