not change < to &lt;

when I insert a source code:
<p><a href="#" title="test <strong>test bold<strong>">test</a></p>
 

after it becomes
<p><a href="#" title="test &lt;strong&gt;test bold&lt;strong&gt;">test</a></p>

why???

the code: title="test <strong>test bold<strong>" need for a tooltip

but if it is changed is not working properly

(google translator)