I received a report about Simple Map. It cannot work with Data form module. There is no errors of javascript. I checked the page and found there is javascropt code window.onload=.. of Data Forum. Because both modules need to add javascript code to window.onload, there is the conflict.  The later module will override the window.onload then other modules need window.onload cannot work properly.

Furtunately, the DotNetNuke provides a API to avoid this kind of conflicts. We can use DotNetNuke.UI.Utilities.DNNClientAPI.AddBodyOnloadEventHandler to register our own window.onload code in server side. The DNN API will manage all on load code to run.

The code can be written in Page_PreRender event handler.

        Private Sub Page_PreRender(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.PreRender
            Try
                  DotNetNuke.UI.Utilities.DNNClientAPI.AddBodyOnloadEventHandler(Me.Page, "mywinload()")
              Catch exc As Exception        'Module failed to load
                ProcessModuleLoadException(Me, exc)
            End Try
        End Sub

 This article is also posed on http://www.zldnn.com/Blog/tabid/569/smid/1896/ArticleID/2788/Default.aspx