No, the fix is only present in 2.9.4-nightly-20150728. If you update the files to the newest nightly build by hand the bug is gone.
What I did to solve the bug:
download and extract the latest nighlty build from: http://ci.newdawnsoftware.com/job/LWJGL-git-dist/lastBuild/
remove all .jar and .jar.sha files from ~/.minecraft/libraries/org/lwjgl/lwjgl/{lwjgl,lwjgl-plattform,lwjgl_util}/2.9.4-nightly-20150209/
copy newest lwjgl.jar to ~/.minecraft/libraries/org/lwjgl/lwjgl/lwjgl/2.9.4-nightly-20150209/lwjgl-2.9.4-nightly-20150209.jar
create shasum of said file
shasum lwjgl-2.9.4-nightly-20150209.jar | sed -e "s/ .*//" > lwjgl-2.9.4-nightly-20150209.jar.sha
repeat 2 previous steps accordingly with lwjgl_util
create jar file from needed native libraries of nightly build
jar cf lwjgl-platform-2.9.4-nightly-20150209-natives-linux.jar liblwjgl* libopenal*
copy jar file to /home/julkip/.minecraft/libraries/org/lwjgl/lwjgl/lwjgl-platform/2.9.4-nightly-20150209
create shasum of this jar
If you start minecraft now, the shiftbug is gone.
It seems that the hashes of the files are no longer stored in the filesystem, but in ~/.minecraft/versions/<version number>/<version number>.json
Unfortunately my tests so far have not been sucessful. It seems that this json-file itself is redownloaded upon the start of the game. Maybe it would be possible to set up a local http-server and direct the download request of this file to it, but that would be just a little bit of overkill.
It would all be much easier if Mojang would just update the library.