in the Win32-port (nh341wn3.zip) there is a tweak included that makes
it possible to re-map keys. This was needed to make some command keys
available to nethack on some non-US keyboards, for example the @-command
(toggle autopickup) on german keyboards (available through AltGr-Q).

Some changes between verion 3.4.0 and 3.4.1 made some of these keys
unavailable, so this tweak has been included.

To re-map the keys (to make them use as they should), follow this
short instructions. You have to start nethack in wizard mode (see
guidebook.txt for instructions) and edit the file defaults.nh (see
your computer's manual for instructions).

To find out what values to enter in the OPTION=subkeyvalue-lines,
follow these instructions:

- comment out all the OPTIONS=subkeyvalue-Lines in your defaults.nh

- prepare a table with all the AltGR-Keys in the first column
  and two more columns

- start nethack in wizard mode (see guidebook)

- start the portdebug-mode

- press the key you want to re-map

- examine the output, for example
PORTDEBUG: ch=171, sc=27, vk=187, pre=126, sh=0x21, ta=0, mk=0

- write down the value for "ch=" in the second column (171)

- write down the value for "pre=" in the third column (126)

- repeat for all AltGR-Keys

Now edit your defaults.nh and enter the two values ch/pre, for example
OPTIONS=subkeyvalue:171/126


HTH,
Sascha