848 Xcart DHL module ustom job

hello, I sell wholesale Towels using X-cart shopping cart and with the help of DHL module which comes with X-cart. I use DHL ground service, I have a discount account setup with DHL GROUND and max you can send with DHL Ground is 150 pounds EACH BOX, I sell one box of 150 pounds and if my customers add more than 2 boxes in there shopping cart the total weight jumps to 300 pounds and DHL give message you cant ship because its over weight or something, What I need is if my customer adds more than 150 pounds the DHL module will divide those two cases like each box should divided to 75 pounds If the overall weight for the whole cart position is greater than 150 pounds, the cart position will be split onto several packages, each of them won't weight greater than 150 pounds. I.e., if the selected quantity is 5 x 75 pounds each, the packages will be as follows: 2 x 75 pounds - 1st package 2 x 75 pounds - 2nd package 1 x 75 pounds - 3rd package In case, if every product weights, say, 120 pounds - each quantity will be shippid as separate package.