I found a bug in my geany 0.20 official ubuntu 11.04 version (0.20-0ubuntu2).
I enabled auto-completion of all words in the document.
When i write a word with a Umlaut in it like "Halbräume"m then autocompletion just suggest "Halbr".
I would expect to get suggested "Halbräume".
Thanks, keep up the good work!