Treating IVS on SVG in OpenType

Hello,

This is onyx. I'm a coordinator of Japanese Emoji and has first
implemented it into the Android in Japan.

As you know, Japanese carriers have an original design for Emoji which is
usually used in mail only and are used the gray scale font for other
applications. However Unicode 6,0 defined a part of these Emoji are unified
the original code which existed in Unicode 5.2. So we need to define to use
either colorful or gray scale with easy implementation to fit each scene of
applications.

And we have to decide this solution ASAP due to transfer the Unicode 6.0
Emoji data with Japanese carrier Email via internet.

My understanding is we can use the colorful or gray scale Emoji separately
if we use this OpenType format. If we need to select the 2 color types data
with each applications, I consider to use the IVS number to use this
purpose. (& easy implementation)

However I couldn't find the descriptions to deal with the IVS number in
this specification. My understanding is:
If IVS number is 0 or nothing, we draw the glyph with gray scale and draw
the colorful Emoji in case of other number (ex. 1).
Is this correct??

Could you let me know your idea about this issue?? Or appropriate
discussion groups??

onyx