VKM3 credit block message

Hi Guru's,

We have an scenario, after creating the sales order and before releasing the document ( VKM3) we activate the " Block Credit Control" in FD32 for that customer account. when user trying to release the document through VKM3, the system is not showing any error message with respect that customer account. but in subsequent process we get message of credit control block. How to bring or intimate the user about "Credit Control" message at the time releasing the document (VKM3 ), please explain.