Newbie: Problem programming AT90CAN128 On STK500 board.

 Hi,
I have a custom made communication gateway PCB with an AT90CAN128
microcontroller meant to control OnPCB components. The PCB card has
its own 6 PIN ISP interface that i connect to the 6 PIN ISP of the
STK500 board. The STK500 board is connected to the PC through the
standard RS232 cable. I am using AVR studio 4 to download the program
onto the controller's flash memory. When i try to access the
controller's flash for programming...it fails. The error says: 'Failed
to enter the programming mode'. I have checked the pin diagrams and
connections. That seems to be okey. I wanted to ask whether the
procedure to program the controller in this way is right or
not? ...Plz help.
When I went through the STK500 manual, it says something about using
STK501 top module for the AT90CAN128. Please explain what this STK501
top module is or where can i find the relevent solution for it?

thanx and regards...
Ravi Pathak