Cannot stop CPU ....

I am trying to get started with Crossworks using a FreeRTOS project that was setup for this environment and my CPU. The CPU is an Atmel AT91SAM7X512. I have a Segger J-link and an Olimex ARM-USB-TINY-H to try. Using the J-Link, I can connect to the board, erase/write flash, and debug the target. No matter what I can think of to try, I can't get the debugger started. It always comes back with the "cannot stop CPU" error message. If I try this on a board that has a runnable program in flash, I see that the LED that is normally blinking stops blinking. So it would appear that the CPU has been stopped. To avoid any question of running code, I erased the flash. The message is the same. This must have a simple cause, but I don't know where to look to further diagnose the problem. The Olimex JTAG interface does not work at all since it is the "TINY-H" model and not the "TINY" which is available on the menu. Any suggestions ?