#3 How to catch Function keys (F1, F2..., ESC etc)

[Bugs]

I've started using telnetd and it works great and is
very stable, I have to say.

Oke, but now my question:
I would like to catch the function keys like F1, F2, F3
etc and ESC.

Some keys are predefined in BasicTerminalIO like
BACKSPACE, but not those mentioned above.

When I log the key value,
I see 1202 after 3 times ESC
and 1202 for F1 .. F4,
for F5 .. F12 I see different nummer
eg. F12 = 1202,52,126
eg. F5 = 1202,53,126

Can I use/catch those keys in TelnetD, and how?