I got this HTTP callback: (sensitive parameters removed)
callback.php?anonymous=false&destination_address=18yeQBiy8YCLLKdHHwK8nRetRz4G2vteYQ&confirmations=1&address=18yeQBiy8YCLLKdHHwK8nRetRz4G2vteYQ&value=-50001&input_address=18yeQBiy8YCLLKdHHwK8nRetRz4G2vteYQ&input_transaction_hash=0b5f18956d8d589cf2bd1b4b01
But I've set up my wallet to send notifications for received transactions only. What's that -50001 value? Why is it negative? It looks like it notified me about an outgoing transaction.