Keyboard shortcuts don't work under Linux if the page content is focused

Hello everyone, I am currently having this problem with Opera under Linux, that is keyboard shortcuts (Ctrl-t, Ctrl-w etc..) when I am focus on the content of the webpage (not the text boxes like the address or search box).

How to reproduce:
1- Open Opera
2- Open a new tab, with any webpage, http://www.amazon.com for example
3- Click in the page, select any text.
4- Press Ctrl-t, Ctrl-w etc... doesn't work
5- Click in the address box, Ctrl-t works again

Versions of Opera tested: 11.60, 11.52, 11.50, 11.10, 11.01, all are 64 bit.
My current OS is Fedora 16, Xorg server version 1.11.2, window manager OpenBox. But I have also tried with Debian 6.02 (GNOME 2 with OpenBox), Fedora 15 (xfce with OpenBox), OpenSUSE 12.1 (KDE 4.7 with Kwin).

Addtional information: I used xwininfo and xev and found out that all the X events are received (KeyRelease etc...) when I press the shortcuts, both when it works and doesn't.
Searching the forum with the keywords "linux keyboard shortcuts" didn't return any similar problem to mine, so I guess I have done something wrong, but trying different distros gave the same result.... so I don't know.
PS: On windows 7 32 bit, it works.

Originally posted by redozu:

3- Click in the page, select any text.
4- Press Ctrl-t, Ctrl-w etc... doesn't work

?? What do you expect to happen? Why do you select text? Ctrl+T opens a new page, Ctrl+W closes the page. Works fine here.

I expect it to open a new page and close the page, here it doesn't do anything.
Selecting some text is to make sure the focus stays in the content frame.

Works fine here on Mageia 1.