Use FCKDialogCommand to oben url?

Hi! It is possible to use FCKDialogCommand to oben an url like http://www.google.de and display this page in the dialog?

I tried the following script...a dialog opens but all i can see is a loading screen...

// Register the related commands.
FCKCommands.RegisterCommand( 'My_Antipirat' , new FCKDialogCommand( 'AntiPirat' , 'AntiPirat' , 'http://www.google.de' , 600, 400 ) ) ;

// Create the  toolbar button.
var oPiratItem = new FCKToolbarButton( 'My_Antipirat', 'AntiPirat' ) ;

oPiratItem.IconPath = FCKConfig.PluginsPath + 'fck_antipirat/fck_antipirat.gif' ;

FCKToolbarItems.RegisterItem( 'My_Antipirat', oPiratItem ) ; // 'My_Antipirat' is the name used in the Toolbar config.