diff --git a/panda/src/downloader/httpChannel.I b/panda/src/downloader/httpChannel.I
index 37172397f9..0d147be377 100644
--- a/panda/src/downloader/httpChannel.I
+++ b/panda/src/downloader/httpChannel.I
@@ -438,6 +438,30 @@ get_bytes_downloaded() const {
   return _bytes_downloaded;
 }
 
+////////////////////////////////////////////////////////////////////
+//     Function: HTTPChannel::get_bytes_requested
+//       Access: Published
+//  Description: When download throttling is in effect
+//               (set_download_throttle() has been set to true) and
+//               non-blocking I/O methods (like begin_get_document())
+//               are used, this returns the number of bytes
+//               "requested" from the server so far: that is, the
+//               theoretical maximum value for get_bytes_downloaded(),
+//               if the server has been keeping up with our demand.
+//
+//               If this number is less than get_bytes_downloaded(),
+//               then the server has not been supplying bytes fast
+//               enough to meet our own download throttle rate.
+//
+//               When download throttling is not in effect, or when
+//               the blocking I/O methods (like get_document(), etc.)
+//               are used, this returns 0.
+////////////////////////////////////////////////////////////////////
+INLINE size_t HTTPChannel::
+get_bytes_requested() const {
+  return _bytes_requested;
+}
+
 ////////////////////////////////////////////////////////////////////
 //     Function: HTTPChannel::is_download_complete
 //       Access: Published
@@ -446,6 +470,14 @@ get_bytes_downloaded() const {
 //               fully downloaded.  If this still returns false after
 //               processing has completed, there was an error in
 //               transmission.
+//
+//               Note that simply testing is_download_complete() does
+//               not prove that the requested document was succesfully
+//               retrieved--you might have just downloaded the "404
+//               not found" stub (for instance) that a server would
+//               provide in response to some error condition.  You
+//               should also check is_valid() to prove that the file
+//               you expected has been successfully retrieved.
 ////////////////////////////////////////////////////////////////////
 INLINE bool HTTPChannel::
 is_download_complete() const {
diff --git a/panda/src/downloader/httpChannel.cxx b/panda/src/downloader/httpChannel.cxx
index 928806b53c..3ca99c22b9 100644
--- a/panda/src/downloader/httpChannel.cxx
+++ b/panda/src/downloader/httpChannel.cxx
@@ -61,6 +61,7 @@ HTTPChannel(HTTPClient *client) :
   _read_index = 0;
   _file_size = 0;
   _bytes_downloaded = 0;
+  _bytes_requested = 0;
   _status_code = 0;
   _status_string = string();
   _proxy = _client->get_proxy();
@@ -221,6 +222,7 @@ run() {
         // Come back later.
         return true;
       }
+      _bytes_requested += _bytes_per_update;
     }
     switch (_download_dest) {
     case DD_none:
@@ -1142,7 +1144,7 @@ run_download_to_file() {
   while (!_body_stream->eof() && !_body_stream->fail()) {
     _download_to_file.put(ch);
     _bytes_downloaded++;
-    if (do_throttle && (++count > _bytes_per_update)) {
+    if (do_throttle && (++count >= _bytes_per_update)) {
       // That's enough for now.
       return true;
     }
@@ -1186,7 +1188,7 @@ run_download_to_ram() {
   while (!_body_stream->eof() && !_body_stream->fail()) {
     _download_to_ramfile->_data += (char)ch;
     _bytes_downloaded++;
-    if (do_throttle && (++count > _bytes_per_update)) {
+    if (do_throttle && (++count >= _bytes_per_update)) {
       // That's enough for now.
       return true;
     }
@@ -1285,6 +1287,7 @@ reset_for_new_request() {
   _last_status_code = 0;
   _file_size = 0;
   _bytes_downloaded = 0;
+  _bytes_requested = 0;
 }
 
 ////////////////////////////////////////////////////////////////////
diff --git a/panda/src/downloader/httpChannel.h b/panda/src/downloader/httpChannel.h
index b42df1f3aa..50833354fe 100644
--- a/panda/src/downloader/httpChannel.h
+++ b/panda/src/downloader/httpChannel.h
@@ -119,6 +119,7 @@ PUBLISHED:
   bool download_to_ram(Ramfile *ramfile);
 
   INLINE size_t get_bytes_downloaded() const;
+  INLINE size_t get_bytes_requested() const;
   INLINE bool is_download_complete() const;
 
 private:
@@ -222,6 +223,7 @@ private:
 
   size_t _file_size;
   size_t _bytes_downloaded;
+  size_t _bytes_requested;
 
   // These members are used to maintain the current state while
   // communicating with the server.  We need to store everything in
diff --git a/panda/src/downloader/httpClient.cxx b/panda/src/downloader/httpClient.cxx
index 618fbad275..dd05946f8d 100644
--- a/panda/src/downloader/httpClient.cxx
+++ b/panda/src/downloader/httpClient.cxx
@@ -110,9 +110,11 @@ HTTPClient::
   // Before we can free the context, we must remove the X509_STORE
   // pointer from it, so it won't be destroyed along with it (this
   // object is shared among all contexts).
-  nassertv(_ssl_ctx->cert_store == _x509_store);
-  _ssl_ctx->cert_store = NULL;
-  SSL_CTX_free(_ssl_ctx);
+  if (_ssl_ctx != (SSL_CTX *)NULL) {
+    nassertv(_ssl_ctx->cert_store == _x509_store);
+    _ssl_ctx->cert_store = NULL;
+    SSL_CTX_free(_ssl_ctx);
+  }
 
   // Free all of the expected server definitions.
   clear_expected_servers();