Vista - Drive Snapshot automation

(I could not find any batch scripting group, so asking for help here.)

I'm stuck here!
I need help on the following script to automate Drive Snapshot. It should
recognizes volumes names on the command line, repeating the snapshot for
each one of them, and -dif parameter to add a -h(lasthashhere) using the
most recent hash on the backup destination, according to the same volume
drive letter (the most recent hash must have the same drive letter of the
volume of the backup).

Naming convention is:
$computername-$disk-$day$month$year-$type.sna

Maybe would be better to set %destdir% as a command line parameter too,
would avoid script edition. This script would be perfect to automate any
backup need, from a scheduled task at a windows server that does a full
backup of various volumes once in a month and another task with daily
differentials, and also to full backup a single computer and his only system
volume c:. (no command line parameters on this scenario)

I hope that I made myself clear Any help would be really appreciated.

@echo off
setlocal

rem (The following line is the only customizable parameter, maybe better as
a command line parameter?)
set destdir=\\temp1\backups
set destdir=%destdir%\%computername%

if not exist %destdir% md %destdir%

if [%1]==[] set %1=c:

:loop
if [%1]==[] goto continue
snapshot.exe %1
%destdir%\$computername-$disk-$day$month$year-$type.sna -Go -T
shift
goto loop

:continue