jquery form plugin

jquery form plugin

i have some different preloader images. and i made a function so i can call it with different id.
function HidePreloader($idPreloader){
      $($idPreloader).hide();
   }

it works fine if i just called it like:
HidePreloader("#orangePreloader");


but when i want to call it in jquery form plugin success event, it wont work at all, my code like this:
$("#formPassword").ajaxForm({
         target:'#container',
         clearForm:true,
         success: HidePreloader("#bluePreloader")
   });

did i write it wrong?