Comment 9 for bug 1247584

I have the exact same issue while running 14.04 with the Logitech Zone Touch T400 mouse.

I can remap the button using udev to another key but udev won't remap to the middle button.

$ sudo udevadm --debug test-builtin keyboard /devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.1/1-1.1:1.2/0003:046D:C52B.0030/input/input41/event6
calling: test-builtin
=== trie on-disk ===
tool version: 204
file size: 5771951 bytes
header size 80 bytes
strings 1271231 bytes
nodes 4500640 bytes
load module index
device 0xa8b860 has devpath '/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.1/1-1.1:1.2/0003:046D:C52B.0030/input/input41/event6'
device 0xa8b860 filled with db file data
Error, unknown key identifier 'middle'
keyboard: mapping scan code 786616 (0xc00b8) to key code 161 (0xa1)
keyboard: mapping scan code 786819 (0xc0183) to key code 226 (0xe2)
keyboard: mapping scan code 786820 (0xc0184) to key code 421 (0x1a5)
keyboard: mapping scan code 786822 (0xc0186) to key code 423 (0x1a7)
keyboard: mapping scan code 786826 (0xc018a) to key code 155 (0x9b)
keyboard: mapping scan code 786830 (0xc018e) to key code 397 (0x18d)
keyboard: mapping scan code 786870 (0xc01b6) to key code 212 (0xd4)
keyboard: mapping scan code 786876 (0xc01bc) to key code 430 (0x1ae)
keyboard: mapping scan code 786977 (0xc0221) to key code 217 (0xd9)
keyboard: mapping scan code 786979 (0xc0223) to key code 172 (0xac)
keyboard: mapping scan code 786989 (0xc022d) to key code 418 (0x1a2)
keyboard: mapping scan code 786990 (0xc022e) to key code 419 (0x1a3)

Notice the line "Error, unknown key identifier 'middle'", I get the same error no matter if I use "middle", "274" or "0x112" (as suggested above by Martin)

This is a regression from the older udev (which used keymaps), which allowed specifying numeric values for the mappings.

I posted here in order not to lose context but I see that the last activity in the bug is from 2013 so if I should open a new bug let me know.

Thanks!