case and strings conversion

I am having trouble understanding strings and
converting of cases. If I want to match something
exaclty in the xsl the case must match exactly. I have
read the prevois posts on changing the case to match
but I am not getting it. How do I convert james to all
lower or all caps to test in xsl. I have the code and
below, but can not figure it out. Thanks.

<xsl:value-of select="translate($string,
'abcdefghijklmnopqrstuvwxyz',
'ABCDEFGHIJKLMNOPQRSTUVWXYZ')"/>


<xml>
     <jim name=JaMeS">
</xml>


__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com