Why do SVG 1.1 Basic validation fail?

To the best of my knowledge this is a valid SVG document:

<?xml version="1.0" standalone="no" encoding="UTF-8"?>
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1 Basic//EN"
  "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11-basic.dtd">

<svg width="100%" height="100%" version="1.1" baseProfile="basic" xmlns="http://www.w3.org/2000/svg">
   <rect x="0" y="0" width="50" height="50"/>
</svg>

The document does not validate on the W3C Validator though. I get errors like 125 "content model is ambiguous". I validate through the File Upload option.

How can I make my document validate?

or

How do I make my docum开发者_运维问答ent valid SVG Basic?

Here are the reference documents which should pass validation (some of them don't pass).

This is one SVG 1.1 Basic document which does pass validation:

<?xml version="1.0" encoding="UTF-8"?>
<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" version="1.1" baseProfile="basic" id="svg-root" width="100%" height="100%" viewBox="0 0 480 360">
    <title id="test-title">color-prop-01-b</title>
    <desc id="test-desc">Test that viewer has the basic capability to process the color property</desc>
    <rect id="test-frame" x="1" y="1" width="478" height="358" fill="none" stroke="#000000"/>
</svg>