Trying to set the value of one form to be the same as the other

Hi,

I am trying to set the value of form with name:
url2ix_2

to be equal to that of:
url2ix_1

But although everything seems to be firing OK, the value of 2 is not changing to that of 1.
Here are the related codes;

function set_equal (\$f, \$ix)
{

var url_a = 'url2ix_' + \$ix;
var url_b = 'url2ix_' + (\$ix + 1);