Contains

Having trouble with contains.  I have a set of elements derived from a
source xml which contains the parts of an email that are bad, that I'd
like to ignore in my result.  An example would be the domain of my
hosting company like so it would be listed as "lfchosting.com" and
another element might be "directnic.com".

So I have:

    <xsl:if test="not(contains($bad_emails_contains,.))">
       ... do my result ...
    </xsl:if>

But not working (not ignoring these emails).  I've also tried

    <xsl:if test="not(contains(.,$bad_emails_contains))">
       ... do my result ...
    </xsl:if>

Any ideas?  Shouldn't this work?

Karl..