BPEL Engine XPATH (non?) compliance

Question

Hi,
what is the level of compliance of BPEL Engine 10.1.3.4 (MLR#8) to XPATH 1.0 or XPATH 2.0?
Specifically, I am interested in boolean() function. XPATH 1.0 and XPATH 2.0 specifications both state the following:
http://www.w3.org/TR/xpath/#function-boolean
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Function: boolean boolean(object)
The boolean function converts its argument to a boolean as follows:
* a number is true if and only if it is neither positive or negative zero nor NaN
* a node-set is true if and only if it is non-empty
* a string is true if and only if its length is non-zero
* an object of a type other than the four basic types is converted to a boolean in a way that is dependent on that type
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http://www.w3.org/TR/xpath-functions/#func-boolean
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15.1.1 fn:boolean
fn:boolean($arg as item()*) as xs:boolean
Summary: Computes the effective boolean value of the sequence $arg. See Section 2.4.3 Effective Boolean ValueXP
* If $arg is the empty sequence, fn:boolean returns false.
* If $arg is a sequence whose first item is a node, fn:boolean returns true.
* If $arg is a singleton value of type xs:boolean or a derived from xs:boolean, fn:boolean returns $arg.
* If $arg is a singleton value of type xs:string or a type derived from xs:string, xs:anyURI or a type derived from xs:anyURI or xs:untypedAtomic, fn:boolean returns false if the operand value has zero length; otherwise it returns true.
* If $arg is a singleton value of any numeric type or a type derived from a numeric type, fn:boolean returns false if the operand value is NaN or is numerically equal to zero; otherwise it returns true.
* In all other cases, fn:boolean raises a type error [err:FORG0006].
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In bpel, if I have a switch with a case expression as boolean(bpws:getVariableData('inputVariable','payload','/client:TestRequest/client:StringValue')), this returns false only if the StringValue element is missing in the inputVariable payload. If the StringValue element is present but is empty like <stringElement/>, then this expression returns true.
Is this a bug?
Thanks,
Shanmu.

Answer 1

bumping up to check if some one can provide more information
Regards,
Shanmu.