You can also use the JTAGICE mkII to prorgam an AVR mounted on the STK503. In order to do this, the AVR's OCD Enable fuse must be set. This fuse can be enabled by ISP Programming or High Voltage Programming.
Turn off the STK500 power switch
Remove the RESET jumper on STK500
Mount a jumper between pin 6 and 8 on the PORTG header on STK503
Connect the JTAGICE probe to the STK503 JTAG connector as shown in Figure 1
Turn on STK500 and JTAGICE power