WHEN AM CREATING SALES ORDER, IF MATERIAL IS NOT AVAILABEL THEN IT SHOULD DIRECTLY CONVERT IT TO PURCHASE ORDER... HOW TO DO IT...

WHEN AM CREATING SALES ORDER, IF MATERIAL IS NOT AVAILABLE THEN IT SHOULD DIRECTLY CONVERT IT TO PURCHASE ORDER... HOW TO DO IT...

i.e in SALES ORDER ITEM CATEGORY SHOULD TO BE CHANGE DIRECTLY FROM TAN TO TAS..... AND PURCHASE ORDER SHOULD BE CREATED AUTOMATICALLY...

GUYS HELP ME OUT  HOW TO DO IT.....

THANKS IN ADVANCE...