Why don't all chars display?

["Dennie, Brooke" <BDennie cas org>]

Hi everyone,

I've been working on getting an iso8859-1 font to display all of
its chars in an entry widget. For some reason I can't get 0xa0 to
display. Here's the code that I'm using:
-----------------------------
char buff[2], *buff2;
GtkWidget *entry;
PangoFontDescription *pfd;

.....

buff[0] = (char)0xa0;
buff[1] = '\0';

gtk_widget_modify_font(entry, pfd);

buff2 = g_convert(buff, -1, "UTF-8", "ISO8859-1", NULL, NULL,
				NULL);
gtk_entry_set_text(GTK_ENTRY(entry), buff2);

.....

-----------------------------

It shows up as just a blank space (it should be a greek alpha). 
When I run this with any other value besides 0xa0, it works just
as I had expected. What am I doing wrong?

Thanks!

Brooke