Specific xpath

Hi all,

I'm working in XHTML with XSLT 1.0 and need to change all relative links
that are in the current folder. That means, I need to pick out local links
that are just a file name "abc_1234.htm" and exclude any that are Internet
(http), links to other folders, that is href="/other_folder" or
href="../another_folder", links to bookmarks href="#top".

At the moment I am matching all links:

<xsl:template match="xhtml:a">

Is it possible to filter link types using the href attribute?

<xsl:template match="xhtml:a[@href='some_expression']" >
or
<xsl:template match="xhtml:a[some_function(@href, string, string)]" >

Is this possible or do I need a more elaborate solution using variables and
parameters?

Thanks,
Richard