Code:
VerticalFieldManager vfm=new VerticalFieldManager(Manager.VERTICAL_SCROLL);
Bitmap DocBitmap=Bitmap.getBitmapResource("100Dossier.jpg ");
BitmapField DocBitmapField=new BitmapField(DocBitmap,BitmapField.FIELD_RIGHT);
HorizontalFieldManager left =new HorizontalFieldManager(Manager.HORIZONTAL_SCROLL);
left.add(DocBitmapField);
HorizontalFieldManager right =new HorizontalFieldManager(Manager.HORIZONTAL_SCROLL);
right.add(sendButton);
vfm.add(left);
vfm.add(right);
add(vfm);
i haven't tested this but this is more or less what you want for a split left right. note you may have to create custom horizontal managers and restrict the width as regardless of Manager.USE_ALL_WIDTH being part of the style, sometimes it tries to fill the screen with them.
tweak it to your needs and try it out.