this is a part of inihilist's guide, i hope it will help...
http://inihilist.wordpress.com/2008/01/07/easy-installation-guide-dual-boot-windows-vista-and-mac-os-x-105-real-quick-and-fool-proof/

31. Once you are inside Vista, put the leopard dvd in the drive. Open the drive from Explorer and copy the “chain0? file in the Leopard DVD root folder ” and copy it in the Windows partition root, i.e, in C:\

32. Remove the Leopard DVD

33. Again, open the “Command prompt” with “Admin” privileges from the Start Menu.

34. Type bcdedit /copy {current} /d “Mac OS X”
Type bcdedit /enum active
Type bcdedit /set {GUID} PATH \chain0

Note: In the first command type {current} as it is, literally..nothing else..just {current} with the brackets. In the 3rd command however, replace the {GUID} with the alphanumeric GUID you see in the enumerated list under MAC OS X. You can see this list on your terminal as soon as you type the 2nd command above.! As far as i know it is the last entry in the this list. Also it is same as the one that shows up after the 1st command.! Its the one besides IDENTIFIER not the one besides resume object.!

For Ex: bcdedit /set {38912a-233fdf-45ghghhg-fdfe4} PATH \chain0

35. Close the terminal, remove any DVD’s if present in the DVD drive and then restart.