Problem when table method is set to weight

Zencart version 1.37
Zone table rate Mod Version 1.1
my product weights are in grams

My problem is that it is not calculating correctly

I have it set the table method to weight i have the zone1 shipping tale set as

1500:4.95,10000:10.00,15000:15.00

now when i select a product with a weight of 1400 and go to the checkout it comes up with

Zones Table Rate (31 x 49.68lbs)
and the shipping charge shows as $153.45 instead of $10


If i set the table method to price it works fine for defined price ranges, but i would like it to work by weight

Any help would be greatly appreciated