images not resizing when inserted into pages

hi, every time i insert an image into a page via Add Media>, and select a size (thumbnail, small, large, full), the image shows up the same size all the time

the image sizes available to me in Add Media> are 150 x 150, 300 x 200 and 470 x 313

i know i could simply upload correctly sized images, but i want to keep the small border and text wp-caption adds to my inserted images

my functions.php

if (function_exists('post-thumbnails'))
    add_theme_support('post-thumbnails');
if (function_exists('add_image_size')) {
    add_image_size('post_thumbnail', 472, 280, true);
    add_image_size('home_post_thumbnail', 193, 138, true);

you can see the problem here:
http://globalaccident.net/about-us/