We're using QNX  to setup a TCP/IP client connection to an embedded device with a very minimal TCP/IP stack.  A bug in 
the embedded server device's stack seems to inject some of the QNX TCP options data into the data section of the first 
syn-ack frame in the three way TCP setup sequence.  When this happens, the QNX TCP/IP stack seems to silently drop the 
frame and the setup never completes.  

The same connection sequence, with a Linux box as the client, is successful.

Attached is a tcpdump, which can be viewed in Wireshark, that shows the detail.  Please see the funny data payload in 
frame #2.  It's weird, but not technically wrong, I think, and should not have been dropped.

192.168.1.2 is the client making the connection
192.168.1.1 is the server receiving it.

Thoughts?

- K.C.