Loadrunner not honoring date/time format

I am doing a SOAP request, and have set the format for the paramater to %Y-%m-%dT00:00:00, but when it submits that request, it is not honoring the defined parameter format.  It always changes it to %Y-%m-%dT00:00:00.000Z format.  I have tried to hard code it, and it does it as well.

Any idea why this is happeneing?

Thanks,

Cody