liberation-fonts/liberation-fonts-sans.conf

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE fontconfig SYSTEM "../fonts.dtd">
<fontconfig>
         <!-- Microsoft -->
        <alias binding="same">
          <family>Arial</family>
            <accept>
              <family>Liberation Sans</family>
            </accept>
        </alias>
        <alias binding="same">
          <family>Liberation Sans</family>
            <default>
              <family>Arial</family>
            </default>
        </alias>
	<!-- for ArialMT -->
	<alias binding="same">
	  <family>ArialMT</family>
	  <accept>
	    <family>Liberation Sans</family>
	  </accept>
	</alias>
	<alias binding="same">
	  <family>Liberation Sans</family>
	  <default>
	    <family>ArialMT</family>
	  </default>
	</alias>
</fontconfig>