[XeTeX] Malayalam typesetting using XeLaTeX

[NMPOST7]

On 13/11/2013 23:58, Zdenek Wagner wrote:
> Just type them on the keyboard, I have looked into AnjaliOldLipi and
> Rachana and both of them contain them. If you want to change
> automatically arabic numerals to the malayalam ones, you can write a
> similar mapping as "devanagarinumerals" in the xetex-devanagari

Thank you Zdenek! Sometimes what is obvious is not seen by the eye or reason! :)
How do I write a mapping for these numerals?

BR
suren