diff --git a/hphp/runtime/debugger/debugger.cpp b/hphp/runtime/debugger/debugger.cpp
index eab811dd0..9781a6594 100644
--- a/hphp/runtime/debugger/debugger.cpp
+++ b/hphp/runtime/debugger/debugger.cpp
@@ -535,7 +535,7 @@ bool Debugger::switchSandbox(DebuggerProxyPtr proxy,
 bool Debugger::switchSandboxImpl(DebuggerProxyPtr proxy,
                                  const StringData* newSid,
                                  bool force) {
-  TRACE(2, "Debugger::switchSandboxImpln");
+  TRACE(2, "Debugger::switchSandboxImpl\n");
   // Take the new sandbox
   DebuggerProxyPtr otherProxy;
   {
@@ -565,7 +565,7 @@ bool Debugger::switchSandboxImpl(DebuggerProxyPtr proxy,
   setDebuggerFlag(newSid, true);
 
   if (otherProxy) {
-    otherProxy->forceQuit();
+    otherProxy->stop();
   }
 
   return true;
diff --git a/hphp/runtime/debugger/debugger_proxy.cpp b/hphp/runtime/debugger/debugger_proxy.cpp
index 5fbf6bd6e..081eb91ad 100644
--- a/hphp/runtime/debugger/debugger_proxy.cpp
+++ b/hphp/runtime/debugger/debugger_proxy.cpp
@@ -364,8 +364,10 @@ void DebuggerProxy::pollSignal() {
   TRACE_RB(2, "DebuggerProxy::pollSignal: ended\n");
 }
 
-// Ask this proxy to stop running and exit cleanly. Used during proxy cleanup,
-// and from the signal polling thread.
+// Ask this proxy to stop running and exit cleanly. Used during proxy
+// cleanup, sandbox switching, and from the signal polling
+// thread. This can be used from a thread which is not stopped at the
+// given proxy's interrupt.
 void DebuggerProxy::stop() {
   TRACE_RB(2, "DebuggerProxy::stop\n");
   DSandboxInfo invalid;
@@ -377,9 +379,9 @@ void DebuggerProxy::stop() {
 
 // Used to quit this proxy, typcially in response to either a quit command from
 // the client or loss of communication with the client. The proxy is removed
-// from the proxy map, ensuring no other threads can use the proxy. It stops
-// the proxy, and then tosses the client exit exception to ensure the current
-// request is terminated with a nice message.
+// from the proxy map, ensuring no other threads can use the proxy.
+// NB: It stops the proxy, and then tosses the client exit exception
+// to ensure the current request is terminated with a nice message.
 void DebuggerProxy::forceQuit() {
   TRACE_RB(2, "DebuggerProxy::forceQuit\n");
   Debugger::RemoveProxy(shared_from_this());
diff --git a/hphp/runtime/debugger/debugger_proxy.h b/hphp/runtime/debugger/debugger_proxy.h
index 86b1338bb..db6ee11d8 100644
--- a/hphp/runtime/debugger/debugger_proxy.h
+++ b/hphp/runtime/debugger/debugger_proxy.h
@@ -99,6 +99,7 @@ public:
 
   void checkStop();
   void forceQuit();
+  void stop();
 
   bool getClientConnectionInfo(VRefParam address, VRefParam port);
 
@@ -112,8 +113,6 @@ private:
 
   void changeBreakPointDepth(CmdInterrupt& cmd);
 
-  void stop();
-
   SmartPtr<Socket> getSocket() { return m_thrift.getSocket(); }
 
   bool m_stopped;