Static credit check

Hi friends,

One of my sold to pary's credit limit was increased. Now when I am doing PGI for sale order which doesn't have any value (total value of the docoument is Rs. 0.00) it is giving static credit limit increased by xxx value. For my scenario this check should be done for the documents which contain value and it should not check for document which doesn't have value. Is it possible? If so how?

Regards

Rama