Scatterplots using rCharts, polychart.js, and Shiny

Question

I'm trying to make a shiny app with a scatterplot and I am getting the error"

Uncaught DefinitionError: Bad specification polychart2.standalone.js:263

I've read that using renderchart2 will fix this but I still get the same error, I am using the latest dev version of rcharts, and this is my code

UI.R

# A bunch of user input
mainPanel(showOutput("data","polycharts"))

server.R

# combined matrix is declared here
shinyServer(function(input, output)
{
    output$data <- renderChart2({
        # x and y are the column headers to be plotted
        plot <- rPlot(x=x,y=y, data=combined_matrix, 
            color = "Categories", facet = "Categories",
            type='point')
        plot$set(dom= 'data')
        return(plot)
})

Thanks for your help