Why does WP auto-complete the a-tag?

If I write a post or a page containi开发者_C百科tg:

<a href="#something"> bla </a>

WP autocompletes it with

<a href="http://www.thewholedamnpath.com/?page_id=291#something">bla</a>

I sincerely don't need this feature, so, what is the way to bypass it?

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Found the solution: http://wordpress.org/extend/plugins/raw-html/

Using the plugin a chunk of code can be wrapped inside [RAW]...[/RAW] tags, and that code will remain untouched by WordPress.