testing an apostrophe

i want to use a recursive template to repalce an apostrophe with "\'". how
can i test that the string contains an apostrophe ? am using:

> <><><><><><><><><><><><><><><><><><><><><><><><><><>
<xsl:when test="contains($sString, ''')">
> <><><><><><><><><><><><><><><><><><><><><><><><><><>
but gives me an error!

Thanks,
Stevenson Ngila
Footman-Walker Associates Ltd
http://www.footman-walker.co.uk




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