[R] Error with spdep

[Perez Martin, Agustin]

Dear useRs:

First of all I would like to thank all the responses.
I've an error with package "spdep".

I am working with a Windows XP machine (AMD-2000-XP RAM-256DDR) and 1.8.0.
R-version and when I try to load spdep appear the following error:

> library(spdep)
Error in loadNamespace(i, c(lib.loc, .libPaths()), keep.source) : 
        There is no package called 'maptools'
Error in library(spdep) : package/namespace load failed

I don't know what is this.
Can you help me?

Best wishes,
Agustin