I've been experiencing this issue. I think I have a possible fix.

luebking wrote:-> shift turns into caps/lock on release.
Did you configure anything (related capslock) in the last tab of "kcmshell4 keyboard"?
What's the output of "setxkbmap -query"?

I have Caps Lock mapped to escape (for vim). Previously, I also had "double shift" mapped to Caps Lock (Keyboard settings -> Advanced -> "Miscellaneous compatibility options" -> "Both shift keys together toggle Caps Lock"). setxkbmap -query looked like this:

Code: Select all

rules:      evdev
model:      pc101
layout:     us,gb
variant:    dvorak,
options:    caps:escape,grp_led:caps,shift:both_capslock,compose:ralt

Clearing the options (setxkbmap -options) fixed the problem. I added them back one at a time, testing after each, and found that the "shift:both_capslock" option was the cause. Disabling the mapping of double shift to caps lock stopped this option from being set.

tl;dr: the "Both shift keys together toggle Caps Lock" option seems to be one possible cause of this problem.

(I'm using KDE 4.8.5 on Kubuntu 12.04 (Precise Pangolin), with Minecraft 1.7.4.)

it *is* the cause of the issue, see mentioned https://bugreports.qt-project.org/browse/QTBUG-26484
It's also the (default?) behavior of the neo layout.