bill@bbrack work $ cat b.xsl
<?xml version="1.0"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0"
   xmlns:date="http://exslt.org/dates-and-times"
   extension-element-prefixes="date"
>
<xsl:template match="/">
date:seconds('1970-01-01T01:00:00+00:00') = <xsl:value-of
        select="date:seconds('1970-01-01T01:00:00+00:00')"/>
date:seconds('1970-01-01T01:00:00+01:00') = <xsl:value-of
        select="date:seconds('1970-01-01T01:00:00+01:00')"/>
</xsl:template>

</xsl:stylesheet>
bill@bbrack work $ xsltproc b.xsl b.xsl
<?xml version="1.0"?>

date:seconds('1970-01-01T01:00:00+00:00') = 3600
date:seconds('1970-01-01T01:00:00+01:00') = 0
bill@bbrack work $ xsltproc --version
Using libxml 20613-CVS2177, libxslt 10110-CVS941 and libexslt 808-CVS941
xsltproc was compiled against libxml 20613, libxslt 10110 and libexslt 808
libxslt 10110 was compiled against libxml 20613
libexslt 808 was compiled against libxml 20613


*** This bug has been marked as a duplicate of 153000 ***

  The release of libxslt-1.1.11 should fix this,
                                                                                
   thanks,
                                                                                
Daniel