[xsl] replacing diacritical marks with combining unicode characters

[Terry Ofner <tofner@xxxxxxxxxxx>]

I have input with many dictionary entries, including copy such as
this edited pronunciation key:

<div class="story">
	<p>PARTIAL PRONUNCIATION KEY</p>
	<p>ay pat, ax pay, 	r care, 
father, ey pet, ex bee </p>
</div>

I need to replace the non-combining characters such as the breve y
(&#728;) with the combining form: (&#774;). Is there a way to set up
a table so that when the processor encounters the &#728; character it
will swap it for the &#774;? Will an ENTITY listing work? Is so,
where does one put such an entity listing?

Terry