Blank web popup

I am incorporating a web popup in my app. It works well enough in the simulator, but in both my iOS and Android device builds, the pop up is blank.

[lua]function scene:createScene( event )

    local sceneView = self.view

    local bg = display.newRect(sceneView, 0,0, display.contentWidth, display.contentHeight )

    bg.anchorX, bg.anchorY = 0,0

    bg:setFillColor(1, 1, 1, 1)    

    bg:addEventListener(“touch”,function (event) native.setKeyboardFocus(nil) end)

    local WebGroup = display:newGroup()

    WebGroup.x = 0;

    WebGroup.y = 0;

    WebGroup.anchorX, WebGroup.anchorY = 0,0

    sceneView:insert(WebGroup)

    local function  URLlistener (event)

        local shouldLoad=true

        local url = event.url

        if (string.find(url, “corona:close”)==1) then

            shouldLoad=false

        end

        return shouldLoad

    end

    local webPopUp = native.showWebPopup( 0, 20, display.contentWidth, display.contentHeight*.8, “http://www.subsurfwiki.org/wiki/Volume”, {urlRequest=URLlistener} )

    local btnClose = widget.newButton(

    {   

        x = display.contentWidth*.5,

        y = display.contentHeight*.9,

        width = 150,

        height = 30,

        onRelease = onHideOverlay,

        label = “Close”,

        labelColor = {default ={0,0,0}, over={0,0,1,1}}

    });

    sceneView:insert(btnClose)  

[/lua]

anyone know why this might be happening?