Version: 0.9.5 (using KDE 4.0.0) Installed from: MS Windows Binaries OS: MS Windows Summary says it all. By the way, currently if you use the back and forward buttons while pointing at a file, it opens the file, treating it like a doubleclick. But that's probably just bug 155574.
Did you have "back" and "forward" action on the RMB popup???
*** This bug has been marked as a duplicate of 155574 ***