I'm using SciTE on ubuntu 13.10 and the key-commands for converting text in upper/lower case (Ctrl+(Shift+)U) don't seem to work (also I noticed they are not documented in the SciTE help page).
Pressing Ctrl+Shift+U and "u" character appears near the selected text as long as the Ctrl+Shift keys are kept pressed.
The "u" character disappear and the text is left unchanged when the Ctrl+Shift keys are released.
I tested both SciTE 3.4.1  and scite 3.3.1 (official version for saucy).
Ubuntu 13.10 (Saucy)
Possibly related bugs: #349 "Ctrl+(Shift+)U are ASCII only".