Reg - server side validation in orbeon forms

hi all ,
    This is srividhya, am working on orbeon and i want to clarify one thing in Orbeon how the validations are to be done at server side. For validations they are using xml schema and some validations are done through xforms bind and my question is how the orbeon server handles the validation at server side, is  they are using some libraries for validation at server side?



With thanks and regards,
N. srividhya