the hasObjectAttribute() of the ezinteger datatype always returns true, even there is no content, this method should probably be something like

    function hasObjectAttributeContent( $contentObjectAttribute )
    {
        // return true;
        return !is_null( $contentObjectAttribute->attribute( 'data_int' ) );
    }

Steps to reproduce

1. create a content class with an ezinteger attribute
2. set no default value
3. create an instance of this class without content in the ezinteger attribute
4. create a template for this class an put something like

{if $node.data_map.integer_attr.has_content}
ezinteger has content ? yes ({$node.data_map.integer_attr.content}) but no !
{/if}

5. the text is always shown