Manually change default os in xp and windows 7 dual-boot

Hello everybody,

I had Windows XP Pro running on my PC and I've installed Windows 7 using dual-boot.

I want to create a command line BAT file that will allow me to change the default OS system before I boot. For example If I'm working on XP and wants 7 to start-up automatically then I'll execute the batch file and it will manipulate the boot info so that i won't have to select it, and if i work in Windos 7 and want to automatically restart to xp i will run another BAT file.

I was able to do it in windows 7 using the command line bcdedit.exe application tha can control any aspect of the boot settings, but i couldn't find anyway to control the boot settings from within XP because the boot "belongs" to windows 7 and XP doesn't even "know it" or able to access it.

However I have a third-party application able to do that called VISTABOOTPRO, so i can assume it is indeed possible, but i want to create a simple one-click procedure to do it for me.

Does anyone know how can i access the boot settings from Windows XP ?

Thanks in advance.