Horizontal Bar Chart and Overlaying Line Chart

I am using SSRS 2008 and developing my reports in BIDS.

I created both data series, originally, as a bar chart. I have clicked on the second series in the "Drop Data Fields Here" area and changed the chart to a line chart. When I do that, it changes both series to a line chart.

However, if I use the column (vertical) chart for the first series, it will let me make the second one a line chart.

Is this a limitation of SSRS 2008? Can I not have one data point be the horizontal bar chart and the second one a line chart?

If so, are there any suggestions how to get around this?

Thanks.