Url.Action does not work in CMS 12?

Hi!

We have just upgraded to CMS 12 and we have this in our view:

<form id="searchbox" action="@Url.Action("Index", "SearchPage")" method="get" autocomplete="off" class="page-searchbox tracked-search">

In CMS 11 I get this: 

<form id="searchbox" action="/sv/admin/soksida" method="get" autocomplete="off" class="page-searchbox tracked-search">

which is correct, but in CMS 12 I get this:

<form id="searchbox" action="/modules/App/SearchPage" method="get" autocomplete="off" class="page-searchbox tracked-search">

What am I missing?

Thanks!

/Kristoffer