diff --git a/checkin_notes b/checkin_notes
index def1a73f74..d58346051a 100644
--- a/checkin_notes
+++ b/checkin_notes
@@ -8350,3 +8350,23 @@ Charlie 14 Oct 2008
         ViewProjects.cpp,.h
         ViewTransfers.cpp,.h
         ViewWork.cpp,.h
+
+David  14 Oct 2008
+    - client: clarify and fix the semantics of "next RPC time".
+        Here's are the new semantics: a scheduler reply can include
+        <next_rpc_delay>
+            Make another RPC ASAP after this amount of time elapses.
+            This is specified by the <next_rpc_delay> element in config.xml.
+        <request_delay>
+            Don't make another RPC until this amount of time elapses.
+            This is sent automatically (and sometimes with large delays)
+            by various parts of the scheduler.
+        next_rpc_delay now "overrides" request_delay in the sense that
+        request_delay is ignored if it's greater than next_rpc_delay.
+
+        In addition: the client maintains a min_rpc_time which is set based
+        on request_delay and also by various exponential backoff schemes.
+        new_rpc_delay now overrides this as well, in the same sense.
+    client/
+        cs_scheduler.cpp
+        work_fetch.cpp
diff --git a/client/cs_scheduler.cpp b/client/cs_scheduler.cpp
index 406b4e8f84..3f82680cf6 100644
--- a/client/cs_scheduler.cpp
+++ b/client/cs_scheduler.cpp
@@ -864,6 +864,15 @@ int CLIENT_STATE::handle_scheduler_reply(
         print_summary();
     }
 
+    // the following must precede the backoff and request_delay checks,
+    // since it overrides them
+    //
+    if (sr.next_rpc_delay) {
+        project->next_rpc_time = now + sr.next_rpc_delay;
+    } else {
+        project->next_rpc_time = 0;
+    }
+
     // if we asked for work and didn't get any,
     // treat it as an RPC failure; back off this project
     //
@@ -874,19 +883,11 @@ int CLIENT_STATE::handle_scheduler_reply(
         project->min_rpc_time = 0;
     }
 
-    // handle delay request from project
-    //
     if (sr.request_delay) {
         double x = now + sr.request_delay;
         project->set_min_rpc_time(x, "requested by project");
     }
 
-    if (sr.next_rpc_delay) {
-        project->next_rpc_time = now + sr.next_rpc_delay;
-    } else {
-        project->next_rpc_time = 0;
-    }
-
     return 0;
 }
 
diff --git a/client/work_fetch.cpp b/client/work_fetch.cpp
index 8ea866c3aa..7b6a688f00 100644
--- a/client/work_fetch.cpp
+++ b/client/work_fetch.cpp
@@ -97,16 +97,16 @@ void CLIENT_STATE::check_project_timeout() {
 }
 
 void PROJECT::set_min_rpc_time(double future_time, const char* reason) {
-    if (future_time > min_rpc_time) {
-        min_rpc_time = future_time;
-		possibly_backed_off = true;
-        if (log_flags.sched_op_debug) {
-            msg_printf(this, MSG_INFO,
-                "[sched_op_debug] Deferring communication for %s",
-                timediff_format(min_rpc_time - gstate.now).c_str()
-            );
-            msg_printf(this, MSG_INFO, "[sched_op_debug] Reason: %s\n", reason);
-        }
+    if (future_time <= min_rpc_time) return;
+    if (next_rpc_time && (future_time > next_rpc_time)) return;
+    min_rpc_time = future_time;
+	possibly_backed_off = true;
+    if (log_flags.sched_op_debug) {
+        msg_printf(this, MSG_INFO,
+            "[sched_op_debug] Deferring communication for %s",
+            timediff_format(min_rpc_time - gstate.now).c_str()
+        );
+        msg_printf(this, MSG_INFO, "[sched_op_debug] Reason: %s\n", reason);
     }
 }
 
@@ -134,7 +134,6 @@ PROJECT* CLIENT_STATE::next_project_master_pending() {
 }
 
 // find a project for which a scheduler RPC is pending
-// and we're not backed off
 //
 PROJECT* CLIENT_STATE::next_project_sched_rpc_pending() {
     unsigned int i;
@@ -142,10 +141,14 @@ PROJECT* CLIENT_STATE::next_project_sched_rpc_pending() {
 
     for (i=0; i<projects.size(); i++) {
         p = projects[i];
-        if (p->waiting_until_min_rpc_time()) continue;
+
+        // project request overrides backoff
+        //
         if (p->next_rpc_time && p->next_rpc_time<now) {
             p->sched_rpc_pending = RPC_REASON_PROJECT_REQ;
             p->next_rpc_time = 0;
+        } else {
+            if (p->waiting_until_min_rpc_time()) continue;
         }
         // if (p->suspended_via_gui) continue;
         // do the RPC even if suspended.
@@ -764,15 +767,18 @@ double RESULT::estimated_cpu_time_uncorrected() {
 
 // estimate how long a result will take on this host
 //
-double RESULT::estimated_cpu_time(bool for_work_fetch) {
 #ifdef SIM
+double RESULT::estimated_cpu_time(bool for_work_fetch) {
     SIM_PROJECT* spp = (SIM_PROJECT*)project;
     if (dual_dcf && for_work_fetch && spp->completions_ratio_mean) {
         return estimated_cpu_time_uncorrected()*spp->completions_ratio_mean;
     }
-#endif
+}
+#else
+double RESULT::estimated_cpu_time(bool) {
     return estimated_cpu_time_uncorrected()*project->duration_correction_factor;
 }
+#endif
 
 double RESULT::estimated_cpu_time_remaining(bool for_work_fetch) {
     if (computing_done()) return 0;