MAIL defines the following default keypad on the VT100/LK201:

           +--------+--------+--------+--------+
           | PF1    | PF2    | PF3    | PF4    |
           |   GOLD |   HELP |EXT/MAIL| ERASE  |
           |        |DIR/FOLD| EXTRACT|SEL MAIL|
           |--------|--------|--------|--------|
           | 7      | 8      | 9      | --     |
           | SEND   | REPLY  |FORWARD |READ/NEW|
           |SEND/EDI|RP/ED/EX|FRWD/EDI|SHOW NEW|
           |--------|--------|--------|--------|
           | 4      | 5      | 6      | ,      |
           | CURRENT|  FIRST |  LAST  | DIR/NEW|
           |CURR/EDI|FIRS/EDI|LAST/EDI|DIR MAIL|
           |--------|--------|--------|--------|
           | 1      | 2      | 3      |ENTER   |
           |  BACK  |  PRINT |   DIR  |        |
           |BACK/EDI|P/P/NOTI|DIR/9999|        |
           |--------+--------|--------| ENTER  |
           | 0               | .      | SELECT |
           |       NEXT      | FILE   |        |
           |     NEXT/EDIT   | DELETE |        |
           +-----------------+--------+--------+