Read data file containing fractional numbers?

Given a text data file with either
space or comma separated items which
may include signed fractional numbers,
such as:

1 0
2 -1/3
3 -1/2
4 -3/5
5 -2/3

or

1,  0
2,  -1/3
3,  -1/2
4,  -3/5
5,  -2/3

how can I use Maxima to read this data into a nested
list of the form
[ [1,0], [2,-1/3], [3, -1/2], [4, -3/5], [5, -2/3] ] .

My attempts with read_nested_list result in things
like

(%i22) fdataL : read_nested_list ("mydata2.dat",comma);
(%o22) [[1, 0], [2, [- 1, /, 3]], [3, [- 1, /, 2]], [4, [- 3, /, 5]],
                                                                 [5, [- 2, 
/, 3]]]

Ted Woollett