Problem with xQuery assertion

Hey,

i have a porblem with importing testCase properties to a assertion. With xpath there is no problem, i do it like this:

 count( ${#TestCase#Count1} )+ count( ${#TestCase#Count2} )-count( ${#TestCase#Count3}) 

But with xQuery, which i originaly want to use the problem appears. i try to do something like that:

<result>[C.1]: 
{
 for $z in *
 let $summe := count( '${TestCase#Count1}' )+ count( '${TestCase#Count2}' )
 return $summe
}
</result>

but this didn't work. the result is always 2. I think because of of the " ' " signs the count-method don't count the number of the values in the result XML,
but the count of the properties. It is possible to transform the xpath statement to a xquery?
Can somebody help me please.