I did mine just writng the code in Visual instead of Text. After adding the code in the Visual screen, the code will created in the manner of

< = &lt; or &#60;
> = &gt; or &#62;
/ = &#47;  	
] = &#93;
[ = &#91;
" = &quot; or &#34;
' = &#39;
“ = &ldquo; or &#8220;
” = &rdquo; or &#8220;
‘ = &lsquo; or &#8216;
’ = &rsquo; or &#8217;
& = &amp; or &#38;

Writing Code in Your Posts
http://codex.wordpress.org/Writing_Code_in_Your_Posts

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