Comment 5 for bug 433926

I too experience this bug with xkb-data 1.6-1ubuntu2 on an up-to-date Karmic.

Applying the patch from upstream helps:

$ diff -ruN /usr/share/X11/xkb/symbols/level3.old /usr/share/X11/xkb/symbols/level3

--- /usr/share/X11/xkb/symbols/level3.old 2009-10-05 13:12:07.839025962 +0200
+++ /usr/share/X11/xkb/symbols/level3 2009-10-05 13:04:32.416525774 +0200
@@ -11,7 +11,7 @@
 default partial modifier_keys
 xkb_symbols "ralt_switch" {
   key <RALT> {
- type[Group1]="ONE_LEVEL",
+ type[Group1]="TWO_LEVEL",
     symbols[Group1] = [ ISO_Level3_Shift ]
     };
   modifier_map Mod5 { ISO_Level3_Shift };