<a> tag duplication

Hello,

I use CKEditor 4.0.1. I am loading XML formatted code and inside the code I have this:

<p><a id="anchor1"/></p>

<p>This text <a class="c1" href="#c1-1" id="id1" title="title1"> is a sample </a>rest of text</p>

When I load this in CKEditor of course it tries to get a valid (X)HTML output, but I get this:

<p></p>
<a id="anchor1"> </a>

<p><a id="anchor1">This text </a><a class="c1" href="#c1-1" id="id1" title="title1"> is a sample </a>rest of text</p>

It seems there is some kind of bug here. Can I avoid or fix it in any manner?

Thanks in advance