Left Division "A\B" of Sparse Matrices is Awfully Slow

It is so slow (cf. below), that it is considered to be a bug!

Scilab
```
--> n=1100;
--> A=speye(n,n)+sprand(n,n,0.001);
--> B=speye(n,n)+sprand(n,n,0.001);
--> tic;A\B;toc
 ans  =
   13.51592
```
Octave
```
octave:7> n=1100;
octave:8> A=speye(n,n)+sprand(n,n,0.001);
octave:9> B=speye(n,n)+sprand(n,n,0.001);
octave:10> tic;A\B;toc
Elapsed time is 0.078903 seconds.
```