The backslash/bar definition is missing from the dvorak variant of the us layout, in the (on my system) /usr/X11R6/lib/X11/xkb/symbols/pc/us file. This means, that switching to a layout that uses this key for something else, such as the Icelandic one - is - and swithing to us(dvorak), the key is still using the Icelandic definition. I found this bug on Solaris Express Community Release build 50 (snv_50), which I believe has Xorg 6.9. This probably applies to all other Xorg versions as well. I'll also bug xkeyboard-config about this. I also have a patch to fix this, but this form does not give an option to upload it. Please tell me what to do with the patch, it's just a one-liner.
Created attachment 7816 [details] [review] Patch to fix backslash/bar in us(dvorak)
I've also bugged xkeyboard-config in https://bugs.freedesktop.org/show_bug.cgi?id=9061 for this, Johann
*** This bug has been marked as a duplicate of bug 9061 ***
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