SD Card Partitioning

[Hassam]

I was Upgrade my Imate-jam with Rom 2.03 TX WWE
But There are lot of bugs in this rom
so now i want to down grade my jam to its previous state but when i enter in bootloader mode Screen shows that

Serial





V 1.00
I plug my usb cable to jam but Serial didnot convert in USB some one told me to downgrade the rom through SD Card
I have 1 GB Kingston mini SD card but now what i have to do now nobody help out me to this trouble i tries lot of searches but invain.
Now i am getting in trouble with my jam kindly some body guide me whole process with files support because i have no files regarding Rom upgrading/Downgrading through SD Card

Thanks a lot..

Hassam Moin
hassam_moin@hotmail.co.uk
hassammoin@yahoo.co.uk