Shortcut for "New Library Folder" not working?

[myrkr]

I assigned a shortcut (Ctrl-F5 for testing) to the function "New Library Folder".
When I open a catalog, select the top level folder or any existing sub folder and press Ctrl-F5, nothing happens.
If I invoke the same function via the context menu (which displays the short cut) the dialog window asking for the folder to create is opened.

Has anyone else the same problem?

My system environment is Ubuntu 11.10 with unity window manager. I checked with xev that the Ctrl-F5 sequence is seen by applications. Other applications (like my editor) has no problems seeing this key combination. I also checked with other keys (like R).