OR expr with node sets

Hi,

i want do something if node
dok/zonen/textsuche/jpk/jpk-titel/div/normfassungen exists
                 or if node
dok/notindexed/jpk/jpk-titel/div/normfassungen exists

But the following xsl:if
<xsl:if test="dok/zonen/textsuche/jpk/jpk-titel/div/normfassungen |
dok/notindexed/jpk/jpk-titel/div/normfassungen">

produces
	java.lang.StringIndexOutOfBoundsException: String index out of
range: -6
using XALAN 2.6.0

What is wrong with the above "or" expr?

Regards,
Thomas.