Trying to Simulating the Interpreter

>  
> hi all,
> im trying to run the InterpreterSimulator and im using
>
> Operating System: WindowsXP Professional
>
> SmalltalkImage current vmVersion.
> >>'Squeak3.10.2 of ''5 June 2008'' [latest update: #7179]'
>
> SmalltalkImage current imageName.
> >>'D:\BC\Squeak\VMM\unix-3.11.3.image'
>    (i downloaded it from the unix site, because it has VMMaker installed)
>
> this image is saved as 'source.image'
>
> i open unix-3.11.3.image  and do
>
> (InterpreterSimulator new openOn:'source.image') test.
>
> >> self error:  'incomaptible image format'
>                       ^^
>                         there's a mistake in message
>
> source image version is 6502 but
> the InterpreterSimulator expects an image version = 6504 ( self
> imageFormatForwardCompatibilityVersion is 6504 )
>
> so where i could find a image version = 6504?
> i tried with several images and im getting the same results.
> maybe im doing something wrong.
>
> thanks in advance.