WebMessageDlg Tmodalresult in webdatamodule

Hi in a TWebDatamodule i'm trying to use frmMain.WebMessageDlg with return procedure (Procedure MsgDlgProc(AValue: TModalResult);) adding unit Vcl.Controls BUT on compilation say me "Identifier not found TModalresult". Can you help me ?

TModalResult is defined in WEBLib.Forms