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ID	KIJ000332	Creation date	April 21, 2006
Platform	Series 40 1st Edition, Series 40 2nd Edition, some S40 3rd Edition devices All Series 40 1st Edition and Series 40 2nd Edition devices	Devices	Nokia 6270, Nokia 6280 (only sw version 3.xx), Nokia 7370, Nokia 6111
Category		Subcategory

Keywords (APIs, classes, methods, functions):

Overview

When using two threads on a single UDP connection, receiving and sending block each other.  

Description

When using two threads on a single UDP connection, receiving and sending block each other.  If an application sets up the receiving thread before sending the first packet, then it will become deadlocked.  Also, while it is waiting for a response from the server, it can’t retry sending.

Solution

Use an alternative implementation method. If possible, always set up a sending thread first.
This is fixed in newer Series 40 3rd Edition devices.