There is something wrong with the work packages list displayed from the context menu of the sprint backlog.
Example: task A and task B are children of Richiesta 1 (user story).
On the list only task A is displayed as child.
See glitch2a.jpg.

The same list from work packages left menu are displayed correctly.
See glitch2b.jpg.

Open Project Community Edition 4.0.5 over Ubuntu 14.04 server.
Windows 7 64bit, dpi 150%, firefox 34.0.5 (the latest version available).

Andrea