[XeTeX] traditional to simplified Chinese character conversion utility or data base

[Daniel Greenhoe]

I know that this is not really the right mailing list for this
question, but I have so far not found the answer by any other means
...

I would like to find or write some a utility that would take an
unicode encoded file and map Chinese traditional characters to
simplified, while leaving all other code points (such  as those in the
Latin and IPA code spaces) untouched. For example, the traditional
character for horse (馬) is at unicode U+99AC, the simplified one (马)
is at unicode U+9A6C, and the Latin character for "A" is at U+0041. So
I want a utility that would change the 99AC to 9A6C, but leave the
0041 unchanged.

Does anyone know of such a utility? Does anyone know of any data base
with a traditional to simplified character mapping such that I could
maybe write the utility myself?

Many thanks in advance,
Dan