diff --git a/src/add-ons/kernel/network/protocols/tcp/BufferQueue.cpp b/src/add-ons/kernel/network/protocols/tcp/BufferQueue.cpp
index 2c03ce361b..89e30ead2f 100644
--- a/src/add-ons/kernel/network/protocols/tcp/BufferQueue.cpp
+++ b/src/add-ons/kernel/network/protocols/tcp/BufferQueue.cpp
@@ -287,10 +287,9 @@ BufferQueue::Get(size_t bytes, bool remove, net_buffer **_buffer)
 	} else {
 		// we can reuse this buffer
 		bytesLeft -= buffer->size;
-		fList.Remove(buffer);
+		fFirstSequence += buffer->size;
 
-		if (fList.First() != NULL)
-			fFirstSequence = fList.First()->sequence;
+		fList.Remove(buffer);
 	}
 
 	// clone/copy the remaining data
@@ -311,11 +310,15 @@ BufferQueue::Get(size_t bytes, bool remove, net_buffer **_buffer)
 
 		// remove either the whole buffer or only the part we cloned
 
+		fFirstSequence += size;
+
 		if (size == source->size) {
 			iterator.Remove();
 			gBufferModule->free(source);
-		} else
+		} else {
 			gBufferModule->remove_header(source, size);
+			source->sequence += size;
+		}
 	}
 
 	if (status == B_OK) {
diff --git a/src/add-ons/kernel/network/protocols/tcp/TCPConnection.cpp b/src/add-ons/kernel/network/protocols/tcp/TCPConnection.cpp
index 355909cf27..60e32dcb5f 100644
--- a/src/add-ons/kernel/network/protocols/tcp/TCPConnection.cpp
+++ b/src/add-ons/kernel/network/protocols/tcp/TCPConnection.cpp
@@ -384,6 +384,19 @@ TCPConnection::SendData(net_buffer *buffer)
 {
 	TRACE(("TCP:%p.SendData()\n", this));
 
+	// TODO: hangs if the buffer size is larger than the maximum!
+	while (fSendQueue.Free() < buffer->size) {
+		status_t status = acquire_sem_etc(fSendLock, 1,
+			B_RELATIVE_TIMEOUT | B_CAN_INTERRUPT, socket->send.timeout);
+		if (status < B_OK)
+			return status;
+	}
+
+	// TODO: check state!
+
+	if (buffer->size == 0)
+		return B_OK;
+
 	RecursiveLocker locker(fLock);
 	fSendQueue.Add(buffer);
 	return _SendQueued();