hot custom_icon modification

[Eduardo Suárez <eduardo ctm ulpgc es>]

Hi,

I'd like to be able to set a default icon to a file/folder from the 
context menu.

I have seen scripts that modify the xml metafiles, but they just work 
for directories that are not open from nautilus, or they need nautilus 
to be restarted.

Someone could point me out how can this be done/where to ask?

Thanks in advance,
-Eduardo