diff --git a/include/libtorrent/torrent.hpp b/include/libtorrent/torrent.hpp
index 3242e8dac..812a81d41 100644
--- a/include/libtorrent/torrent.hpp
+++ b/include/libtorrent/torrent.hpp
@@ -407,7 +407,7 @@ namespace libtorrent
 		{ return m_num_uploads < m_max_uploads; }
 
 		bool choke_peer(peer_connection& c);
-		bool unchoke_peer(peer_connection& c);
+		bool unchoke_peer(peer_connection& c, bool optimistic = false);
 
 		// used by peer_connection to attach itself to a torrent
 		// since incoming connections don't know what torrent
diff --git a/src/session_impl.cpp b/src/session_impl.cpp
index 3636d8344..753b9641a 100644
--- a/src/session_impl.cpp
+++ b/src/session_impl.cpp
@@ -2807,11 +2807,19 @@ namespace aux {
 				if (!pi->optimistically_unchoked)
 				{
 					torrent* t = pi->connection->associated_torrent().lock().get();
-					bool ret = t->unchoke_peer(*pi->connection);
+					bool ret = t->unchoke_peer(*pi->connection, true);
 					TORRENT_ASSERT(ret);
-					pi->optimistically_unchoked = true;
-					++m_num_unchoked;
-					pi->last_optimistically_unchoked = session_time();
+					if (ret)
+					{
+						pi->optimistically_unchoked = true;
+						++m_num_unchoked;
+						pi->last_optimistically_unchoked = session_time();
+					}
+					else
+					{
+						// we failed to unchoke it, increment the count again
+						++num_opt_unchoke;
+					}
 				}
 			}
 			else
diff --git a/src/torrent.cpp b/src/torrent.cpp
index 52c80e2e8..167cdb5f4 100644
--- a/src/torrent.cpp
+++ b/src/torrent.cpp
@@ -3220,13 +3220,16 @@ namespace libtorrent
 		return true;
 	}
 	
-	bool torrent::unchoke_peer(peer_connection& c)
+	bool torrent::unchoke_peer(peer_connection& c, bool optimistic)
 	{
 		INVARIANT_CHECK;
 
 		TORRENT_ASSERT(c.is_choked());
 		TORRENT_ASSERT(!c.ignore_unchoke_slots());
-		if (m_num_uploads >= m_max_uploads) return false;
+		// when we're unchoking the optimistic slots, we might
+		// exceed the limit temporarily while we're iterating
+		// over the peers
+		if (m_num_uploads >= m_max_uploads && !optimistic) return false;
 		if (!c.send_unchoke()) return false;
 		++m_num_uploads;
 		return true;