[R] Map with no political border

[Julien Million]

Hi,

I would like to plot a map without political borders, but not black... I
am mainly using the maps package, and wanted to know if it was possible
with this one, or if I should use something else, like shape file.

If I do

library(maps)
map(fill=T)

I have a map of the world filled in black. I would like to do the same but
with another color and with no political borders (only filled land areas).
If I do

map(fill=T, col=³blue²)

the borders are automatically added, and I cannot find a way to remove
them as the parameters boundary or interior are ignored if fill is true.

Thanks a lot

Julien