Invalid date value in SOAP Response

Hi,

I've got difficulties to use properties in a soap response. 

When using this syntax:

<ns:currentTime>2019-01-29T14:45:32.345Z</ns:currentTime>, no problems the syntax is Valid regarding the wdsl file given to SoapUI.

I try to replace the fixed string 2019-01-29T14:45:32.345Z by a project property defined as:

Name = dateTime and Value = 2019-01-29T14:45:32.345Z

And use it like this

<ns:currentTime>${Project#dateTime}</ns:currentTime>

The result is Invalid date value: ${Project#dateTime}

ns:currentTime is an xml s:dateTime

Where do I make a mistake ? Thanks.