iExpense self approval after receiving the approval delegation from a manager

Payable iExpense Guru

We are seening a scenrio in our iExpense processing that a iExpense user can self approve his or her expense.
The scenario is as If a manager set his vaction rule in such that delegate the authority of all expense approval reports to his peer(Mr A) for two weeks while he is out of office.
Then Mr A can submit an iExpense for himself and submit to the manager who is out office for approval. Since Mr A is receiving his manager's delegation expense reports then the expense from Mr A will come to himself as a redirect since his Manager delagte all expense approval to him for 2 weeks.