Bug when adding anchor tag with apostrophe in href:

For example: go to HTML mode and paste the following:

<a href="BLOCKED SCRIPT window.confirm('close window?');">test link</a>

Then switch back to Normal mode.  Switch back again to HTML code and you'll see that the source code has been changed to:

<a href="BLOCKED SCRIPT window.confirm(" close window?');"close window?');">test link</a>

This is a critical issue for us because we have all sorts of existing content which gets mangled simply by opening a content that contains anchor tags with apostrophe in href.  Thank you for any help/assistance on this.