Sort order for Simplified Chinese (pinyin)

FrameMaker 10 (Windows)

It seems that if I specify the sort order for Simplified Chinese (pinyin) on the reference page,

index entries that start with "i" and "v" are not shown under their corresponding group titles.

(I assume that this may be due to the fact that pinyin words never start with these letters.)

If I have an entry that starts with an English word like "IP," it appears under the "J" group.

I want the entry to appear under the "I" group. How can I do this?

I have the IX reference page set up as follows:

GroupTitlesIX paragraph

Symbols[\];Numerics[0];A;B;C;D;E;F;G;H;I;J;K;L;M;N;O;P;Q;R;S;T;U;V;W;X;Y;Z;

SortOrderIX paragraph

<$symbols><$numerics><$alphabetics><$pinyin>

I've also tried:

SortOrderIX paragraph

<$symbols><$numerics><$pinyin>

Thanks in advance.

Tak Osato