Security in the area has improved. However, check to see if you need to worry before leaving south. Go to the office of the district commisoner for information, or go to the Red Cross branch, located above the KCB, and they can call the commissioner for you and give you their opinion.
banking
There are banks on both the Kenyan and the Ethiopian side. The KCB on the Kenyan side has an ATM. Only money exchangers will buy or sell birr for shillings--the rates are horrible. Try stores on the Kenyan side for exchange instead of street touts.