[xsl] Translate characters in a string

["M. Carlson" <mulligh@xxxxxxxxxxx>]

Hi!  I have a series of strings that look like this:

<item>Technical writer%aAnalytical approach%bPractical matters</item>

I want to output this in HTML as:

Technical writer--Analytical approach--Practical matters

So in other words, I wants to translate % and the character following it (a, 
b, c, etc.) into a hyphen character.  I'm sure I need to use some type of 
recursive template, but am not sure how to put it all together.

Thanks for any help.

Mulligh