diff --git a/indra/llmessage/aicurlthread.cpp b/indra/llmessage/aicurlthread.cpp
index 6234e9425..64b35c683 100644
--- a/indra/llmessage/aicurlthread.cpp
+++ b/indra/llmessage/aicurlthread.cpp
@@ -806,7 +806,15 @@ void CurlSocketInfo::set_action(int action)
   if ((toggle_action & CURL_POLL_OUT))
   {
 	if ((action & CURL_POLL_OUT))
+	{
 	  mMultiHandle.mWritePollSet->add(this);
+	  if (mTimeout)
+	  {
+		  // Note that this detection normally doesn't work because mTimeout will be zero.
+		  // However, it works in the case of a redirect - and then we need it.
+		  mTimeout->upload_starting();			// Update timeout administration.
+	  }
+	}
 	else
 	{
 	  mMultiHandle.mWritePollSet->remove(this);
@@ -2140,6 +2148,11 @@ size_t BufferedCurlEasyRequest::curlHeaderCallback(char* data, size_t size, size
 	self_w->received_HTTP_header();
 	self_w->setStatusAndReason(status, reason);
 	done = true;
+	if (status >= 300 && status < 400)
+	{
+	  // Timeout administration needs to know if we're being redirected.
+	  self_w->httptimeout()->being_redirected();
+	}
   }
   // Update timeout administration. This must be done after the status is already known.
   if (self_w->httptimeout()->data_received(header_len/*,*/ ASSERT_ONLY_COMMA(self_w->upload_error_status())))
diff --git a/indra/llmessage/aihttptimeout.cpp b/indra/llmessage/aihttptimeout.cpp
index 352862ca1..0f99e23d2 100644
--- a/indra/llmessage/aihttptimeout.cpp
+++ b/indra/llmessage/aihttptimeout.cpp
@@ -133,6 +133,20 @@ void HTTPTimeout::reset_lowspeed(void)
   DoutCurl("reset_lowspeed: mLowSpeedClock = " << mLowSpeedClock << "; mStalled = -1");
 }
 
+void HTTPTimeout::being_redirected(void)
+{
+  mBeingRedirected = true;
+}
+
+void HTTPTimeout::upload_starting(void)
+{
+  // We're not supposed start with an upload when it already finished, unless we're being redirected.
+  llassert(!mUploadFinished || mBeingRedirected);
+  mUploadFinished = false;
+  // Apparently there is something to upload. Start detecting low speed timeouts.
+  reset_lowspeed();
+}
+
 // CURL-THREAD
 // This is called when everything we had to send to the server has been sent.
 //                                                    <-----mLowSpeedOn------>
@@ -143,7 +157,9 @@ void HTTPTimeout::upload_finished(void)
 {
   llassert(!mUploadFinished);	// If we get here twice, then the 'upload finished' detection failed.
   mUploadFinished = true;
-  // We finished uploading (if there was a body to upload at all), so not more transfer rate timeouts.
+  // Only accept a call to upload_starting() if being_redirected() is called after this point.
+  mBeingRedirected = false;
+  // We finished uploading (if there was a body to upload at all), so no more transfer rate timeouts.
   mLowSpeedOn = false;
   // Timeout if the server doesn't reply quick enough.
   mStalled = sClockCount + mPolicy->getReplyDelay() / sClockWidth;
@@ -179,11 +195,6 @@ bool HTTPTimeout::data_received(size_t n/*,*/
 	  // 'Upload finished' detection failed, generate it now.
 	  upload_finished();
 	}
-	// Turn this flag off again now that we received data, so that if 'upload_finished()' is called again
-	// for a future upload on the same descriptor, then that won't trigger an assert.
-	// Note that because we also set mNothingReceivedYet here, we won't enter this code block anymore,
-	// so it's safe to do this.
-	mUploadFinished = false;
 	// Mark that something was received.
 	mNothingReceivedYet = false;
 	// We received something; switch to getLowSpeedLimit()/getLowSpeedTime().
diff --git a/indra/llmessage/aihttptimeout.h b/indra/llmessage/aihttptimeout.h
index aa5e6feef..2c5442075 100644
--- a/indra/llmessage/aihttptimeout.h
+++ b/indra/llmessage/aihttptimeout.h
@@ -77,9 +77,10 @@ class HTTPTimeout : public LLRefCount {
 	AIHTTPTimeoutPolicy const* mPolicy;			// A pointer to the used timeout policy.
 	std::vector<U32> mBuckets;					// An array with the number of bytes transfered in each second.
 	U16 mBucket;								// The bucket corresponding to mLastSecond.
-	bool mNothingReceivedYet;					// Set when created, reset when the HTML reply header from the server is received.
+	bool mNothingReceivedYet;					// Set when created, reset when the first HTML reply header from the server is received.
 	bool mLowSpeedOn;							// Set while uploading or downloading data.
 	bool mLastBytesSent;						// Set when the last bytes were sent to libcurl to be uploaded.
+	bool mBeingRedirected;						// Set when a 302 header is received, reset when upload finished is detected.
 	bool mUploadFinished;						// Used to keep track of whether upload_finished was called yet.
 	S32 mLastSecond;							// The time at which lowspeed() was last called, in seconds since mLowSpeedClock.
 	S32 mOverwriteSecond;						// The second at which the first bucket of this transfer will be overwritten.
@@ -95,12 +96,18 @@ class HTTPTimeout : public LLRefCount {
 
   public:
 	HTTPTimeout(AIHTTPTimeoutPolicy const* policy, ThreadSafeBufferedCurlEasyRequest* lock_obj) :
-		mPolicy(policy), mNothingReceivedYet(true), mLowSpeedOn(false), mLastBytesSent(false), mUploadFinished(false), mStalled((U64)-1)
+		mPolicy(policy), mNothingReceivedYet(true), mLowSpeedOn(false), mLastBytesSent(false), mBeingRedirected(false), mUploadFinished(false), mStalled((U64)-1)
 #if defined(CWDEBUG) || defined(DEBUG_CURLIO)
 		, mLockObj(lock_obj)
 #endif
 		{ }
 
+	// Called when a redirect header is received.
+	void being_redirected(void);
+
+	// Called when curl makes the socket writable (again).
+	void upload_starting(void);
+
 	// Called when everything we had to send to the server has been sent.
 	void upload_finished(void);
 
diff --git a/indra/newview/floatervoicelicense.cpp b/indra/newview/floatervoicelicense.cpp
index 17dff4a5e..93d403744 100644
--- a/indra/newview/floatervoicelicense.cpp
+++ b/indra/newview/floatervoicelicense.cpp
@@ -104,6 +104,7 @@ class LLIamHereVoice : public LLHTTPClient::ResponderWithResult
 		};
 
 		/*virtual*/ AIHTTPTimeoutPolicy const& getHTTPTimeoutPolicy(void) const { return iamHereVoice_timeout; }
+		/*virtual*/ bool redirect_status_ok(void) const { return true; }
 		/*virtual*/ char const* getName(void) const { return "LLIamHereVoice"; }
 };
 
diff --git a/indra/newview/llfloatertos.cpp b/indra/newview/llfloatertos.cpp
index e58b1783e..700479406 100644
--- a/indra/newview/llfloatertos.cpp
+++ b/indra/newview/llfloatertos.cpp
@@ -132,6 +132,7 @@ class LLIamHere : public LLHTTPClient::ResponderWithResult
 		};
 
 		/*virtual*/  AIHTTPTimeoutPolicy const& getHTTPTimeoutPolicy(void) const { return iamHere_timeout; }
+		/*virtual*/ bool redirect_status_ok(void) const { return true; }
 		/*virtual*/ char const* getName(void) const { return "LLIamHere"; }
 };