ROM backup

[JMorrison]

hi peoples.i have a question:i have a tytn 2 with this rom specifications
ROM version:1.56.405.5
ROM date:08/28/07
Radio version:1.27.12.32
Protocol version:22.45.88.07H
i have warranties for 2 years for my device so if i burn a new rom version (wm 6.1) i lost Warranties.if some one can tell my how i can backup my existing rom version please help me or a link with version of the above.thx

[Nghiem]

READ WIKI (http://wiki.xda-developers.com/index.php?pagename=HTC_Kaiser) and/or G.W.E.N.I. (http://forum.xda-developers.com/showthread.php?t=369282)

[ady_uaic]

nghiem i cannot also find a backup modality on that links.