SWFTextField_setFontCharacter(3) this is called when the textfield is added to the movie,

SYNOPSIS

#include <ming.h>

void SWFTextField_setFontCharacter
(
       SWFTextField field,

       SWFFontCharacter fontchar

);

PARAMETERS

SWFTextField field
Not Documented.
SWFFontCharacter fontchar
Not Documented.

DESCRIPTION

So no more changes to it from that point other type may still add characters to the fontchar.