cals-tables

I'm getting crazy with spanning cells of a table. My table is of 3 columns. Below you see one row (only fragment): <tgroup> <colspec name="x"> <colspec name="y"> <colspec name="z"> <tbody> <row> <entry>abc <entry namest="y" nameend="z">blabla The second entry (blabla) should span two entry (=table cells). The information is in the attributes "nameend" and "namest". My way is: xsl:template match="entry" ... get the position number of <colspec name=z> (here 3) and of <colspec name="y"> (here 2) <??????> substract z and y (=1) add 1: result=3 <xsl:param name="colspan"> <xsl:value-of select="(