Mini 6410 image length error

Mitsokalis Vangelis
Hi everybody.
I recently have built my own WinCE 6.0 English image for the mini 6410,
using the necessary tools. My image boots and runs successfully from the SD
card. 
But when I am trying to run it from the flash I am getting an “image length
error” thru the serial port. 
(I have successfully flashed the image on the device) 
I have read that maybe I need to update the boot loader via JTAG but I am
not so sure and I don’t know how to do it, because there is no any H-JTAG
and supervivi supplied with the mini 6410.  
Any ideas?