Custom Code Workflows with Office 365 SharePoint

Hi,

I can't find much information about the cloud version of Sharepoint using Office 365.  If I have a SharePoint workflow that was created in Visual Studio and has custom C# code in some of it's activities, will I be able to import that into an Office 365 solution?  Or do only workflows created using SharePoint Designer (no code) work in the cloud SharePoint?

Thanks!