Opening screenshots from chat does not work on Linux

Clicking on the highlighted part of the "Saved screenshot as..." part yields no results, but an error message in the log:

Client> 2013-09-12 20:58:39 [CLIENT] [INFO] [CHAT] Saved screenshot as 2013-09-12_20.58.38.png
Client> env: wine: File or directory not found

It apparently tries to open the screenshot using wine, while the better choice would be to use "xdg-open", which selects the appropriate image viewer based on user preference.