ctrl-O is used to jump to the previous entry in the jump list. But in the IDE, according to the documentation, ctrl-O helps you override methods declared in a base class, kind of like ctrl-enter in Eclipse when the cursor is on an empty line.
One can change a setting that will assign the control of ctrl-O to the IDE. That would make vim loose access to that key, and you'd no longer can use it to jump around the jump list.
Is there a special shortcut key, so that the next key is handled by the IDE instead of vim?