You can do it in grub (recommended)
Post the result of these commands (run as root):
OR you can try it through windows (did not work for me), Quoting from: http://enterprise.linux.com/article....tid=129&tid=49
linux:/home/user # dd if=/dev/hdb4 of=bootsect.lnx cbs=512 count=1
1+0 records in
1+0 records out
512 bytes (512 B) copied, 0.009368 seconds, 54.7 kB/s
chown user bootsect.lnx
To complete the transplant, place the file you created with dd or Bootpart on the Windows drive as C:\bootsect.lnx.
Now it's time to tell Windows about Linux. Again, there are two ways to go about this.
If you are doing everything manually,
fire up a text editor in Windows and edit the file c:\boot.ini. Add the line c:\bootsect.lnx="Linux" to the end of the file.