Amount Sort using Abs Value

[courtney]

When I sort by amount it sorts by absolute value, i.e. ascending:
$8.00
($9.00)
$10.00
($11.00)
It should sort low to high:
($11.00)
($9.00)
$8.00
$10.00

[naviline]

It should sort by absolute amount...

(11.00)
(10.95)
5.00
18.00

Thanks!