"ellipsize" PANGO_ELLIPSIZE_END .vs. PANGO_ELLIPSIZE_MIDDLE

[Van H Tran <tvhoang1980 yahoo com>]

Hi all,
I am trying to make my Gtktreeview able to truncate
the long text rows by doing this

    textRenderer = gtk_cell_renderer_text_new();

    /* Make the rows able to ellipzise (truncate with
...) the text */
    g_object_set(G_OBJECT(textRenderer), "ellipsize",
PANGO_ELLIPSIZE_END, NULL);
    gtk_cell_renderer_set_fixed_size(textRenderer,
CELL_RENDERER_WIDTH, -1);

This works all fine. However, if i tried with
PANGO_ELLIPSIZE_MIDDLE, it doesn't ellipsize in the
middle, it only replaces the end of the text with the
"...", just like PANGO_ELLIPSIZE_END.

Am i missing something?
Thanks in advance