[R] From Distance Matrix to 2D coordinates

[Lorenzo Isella]

Dear All,
I am struggling with the following problem: I am given a NxN symmetric 
matrix P ( P[i,i]=0, i=1...N and P[i,j]>0 for i!=j) which stands for the 
relative distances of N points.
I would like use it to get the coordinates of the N points in a 2D 
plane. Of course, the solution is not unique (given one solution, I can 
translate or rotate all the points by the same amount and generate 
another solution), but any correct solution will do for me.
Any idea about how I can achieve that? Is there any clustering package 
that can help me?
Many thanks.

Lorenzo