need help: got a problem when using openocd's load_image

I just meet an error when using openocd to load an bin format image to the board(mini2440).

when I execute command: load_image 2440test_N35.bin 0x30000000 bin

and it give an promp: invalid elf header

it is strange that openocd check the image as a elf format as i have already specify the format to bin in command.

it will be appreciate anyone can help!