How to remove "removable device icons" in Save as dialog

Hi,

When I use some applications (such as gedit, Epiphany web browser) and
click "Save"/"Save as" icon on toolbar, a normal "Save as" dialog pop up
as followed:

Name:
Save in folder:  Home 
> Browse for other folder 

If I click "Home" or "Browse for other folders", I can get a list as
followed:

Home
Desktop
Filesystem
Floppy
floppy-usb (optional, if connecting USB floppy drive)
floppy-usb2 (optional, if connecting USB floppy drive)
CD-ROM

How can I remove all the removable device icon from it (including
Floppy, floppy-usb, floppy-usb2, CD-ROM)? Is there any configuration in
gconf to do it?

Thanks.

Rocky