Doesn't work with '-' in delta

With 'green-block|Green' it doesn't use a template with file name 'block--blocktheme--green-block.tpl.php'

in blocktheme.module on line #322
$variables['theme_hook_suggestions'][] = 'block__blocktheme__' . $custom_block_theme;

replace it with:
$variables['theme_hook_suggestions'][] = 'block__blocktheme__' . str_replace('-', '_', $custom_block_theme);