Movement of columns in GtkTreeView

[AlannY <m alanny ru>]

Hi there, my name is Alan.

Recently, I found that one of my favorite application (Banshee, media 
player, u no) has a weird functionality of GtkTreeView. I think that is 
that application *feature*, but I want to implement similar feature in 
my app.

So, that is the feature? In my app, I have a GtkTreeView with columns 
etc. But I can't change position of columns. I'm really don't know how 
to explain it, so I record some test movie of my desktop. It's on Youtube:

http://ru.youtube.com/watch?v=4UKpnKAUO_8

How to move column from (for example) position most left to position 
most right?

Before:
+---------------------------+
| GtkTreeView               |
| +----------+ +----------+ |
| | Column 1 | | Column 2 | |
| +----------+ +----------+ |
+---------------------------+

After:
+---------------------------+
| GtkTreeView               |
| +----------+ +----------+ |
| | Column 2 | | Column 1 | |
| +----------+ +----------+ |
+---------------------------+

I mean, do it not from my program, but by user movements, like 
Drag-and-Drop (like on video).

Thank you.