GL account segments on Expense report template

When I define a default account for an expense item on an expense report template, I normally do not have to enter a value for every segment of the account because it gets combined with the employee's GL Account during Payables Invoice Import. But in our R12 instance, when I tried to leave cost center segment of the GL account blank in the report template, the segment defaulted back to the constant value "000" after I click "OK".  As a result, the cost center of the distributions on my expense reports is not deriving from employee record but from template.

Any suggestions?