Win32, Alt-Sysreq & Terminal Servers

Just noticed a problem - alt-sys request doesn't seem to do anything
when using tn5250 via a terminal servers (both RDP and ICA).  On the
same terminal at the console this works.
 
Nothing appears in the trace file when the keys are pressed.   The same
key combinations works fine for teemtalk (another 5250 emulator).
 
Any hints?  While I'm very rusty at c coding (nor did I ever get to the
level required for this sort of project), but I have patched the code
for destructive backspaces using the patch from the mailing list, so I
can re-compile the code if needed.
 
 (I've tested the normal version to make sure the changes this didn't
cause the problem).
 
I've tried the unix_sysreq option and this works, however this is not an
acceptable work around according to the Projects team.  Its either get
this working or buy some very expensive site licenses :S


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