Could you supply the version of Ubuntu (cat /etc/issue) and the version of kaddresbook (dpkg-query -W kaddressbook) ?
In my test, on Kubuntu Gutsy, with kmail 4:3.5.7enterprise20070926-0ubuntu2, I have assigned 'Mark as Important' to Ctrl-I successfully, and kmail remembers it (after closing, even rebooting). In my Settings->Configure Shortcuts, I don't have an option for "Filter Classify as spam".
Could you try to assign 'Mark message as Important' to Ctrl-I and see if that sticks ? If so, could you assign it to Ctrl-J and see if it sticks ?
Could you supply the version of Ubuntu (cat /etc/issue) and the version of kaddresbook (dpkg-query -W kaddressbook) ?
In my test, on Kubuntu Gutsy, with kmail 4:3.5.7enterpri se20070926- 0ubuntu2, I have assigned 'Mark as Important' to Ctrl-I successfully, and kmail remembers it (after closing, even rebooting). In my Settings->Configure Shortcuts, I don't have an option for "Filter Classify as spam".
Could you try to assign 'Mark message as Important' to Ctrl-I and see if that sticks ? If so, could you assign it to Ctrl-J and see if it sticks ?