Error in date add

Hi!

I encountered an error using the date:add  with an duration like -PT31M 
on 2004-11-12T08:30 this results to
2004-11-12T07:0-1

In file date/functions/add/date.add.function.xsl  i replaced the 
following code:
...
<<xsl:value-of select="*format-number($new-minute mod 60, '00')*" />
  <xsl:text>:</xsl:text>
  <xsl:if test="*$new-second mod 60 < 10*">0</xsl:if>
  <xsl:value-of select="*$new-second mod 60*" />


with
<xsl:value-of select="format-number(($new-minute + 60) mod 60, '00')" />
<xsl:text>:</xsl:text>
<xsl:value-of select="format-number(($new-second + 60) mod 60, '00')" />
....

and now it seems to work properly.  Was there a specific reason to 
handle seconds different than minutes?


cheers
         Michael Knümann