Hallo Holger,
laut dem IBM Dokument muss es aber mit dem Parameter gehen:

Calling another Program from within VBScript Macro: PCOMM now supports starting an application file from within a
VBScript. To accomplish this a new automation object has been introduced. autSystem is the new object and Shell
is the new method.
The prototype is as follows:
function autSystem.Shell "ExeName",["Parameters"],[WindowStyle] as long
Parameters :
ExeName - String; the path and filename to the executable file.
Parameters - String, optional; any parameters you wish to pass on to
the application
WindowStyle - Integer, optional; the window style that you want the
application started as.
The valid values are:
AUTSYS_SHOW = 1 - show normal with focus
AUTSYS_SHOWMINIMIZED = 2 - show minimized with focus
AUTSYS_MAXIMIZE = 3 - show maximized
AUTSYS_SHOWNA = 4 - show normal without focus
AUTSYS_MINIMIZE = 5 - show minimized without focus
The default is AUTSYS_SHOW.
Return:
long - If the value is less than 32 it indicates an error has occured.
example: to run notepad from within a VBScript
autSystem.Shell "Notepad.exe", "c:\test.txt" , 1
This will start notepad with the file c:\test.txt loaded in a Normal window with focus.