Don't use Acronis or Ghose, there's a free alternative...
Grab BartPE Builder (
http://www.nu2.nu/pebuilder/download/) and DriveImage XML (
http://www.runtime.org/dixml.htm)... Not sure if you're familiar with the idea of a Live CD, but basically BartPE will take your (legit) Windows install CD and turn it into a "Live CD", which is a version of Windows which is totally self-enclosed and bootable off the CD... The DriveImage XML program needs to be installed in the BartPE Builder as well, or else the Live CD won't have that plugin available...
Once you've got your Live CD with the DriveImage plugin, here's what you do:
1) Boot into OS X
2) Connect a USB hard drive, to which you're gonna copy the image of the Bootcamp partition (I've only tried USB but Firewire may well work as well)
3) Reboot the computer while holding down the Alt key... you'll get the startup disc menu... Select the CD
4) The Live CD will boot... when you've got the desktop, find the menu and navigate to the DriveImage XML plugin...
5) Follow the instructions in DriveImage XML - basically you select the partition you want to backup, select a destination (the USB disc) and it just does its thing...
To restore a partition just reboot into the Live CD and launch DriveImage XML as above, select the target partition on your Mac, and then select the backed up version on you USB disc...
One thing though - if you want the USB drive to be visible to the Live CD, it has to be plugged in and turned on BEFORE the CD starts booting... you can even leave it as late as turning it on while the initial Alt-key startup disc menu is still being displayed, but make sure it's on before you start booting into the Live CD or it won't see the drive...