Has anyone had success with creating custom error bars in Excel 2007 from VBA?

In prior versions I was able to do so with

ActiveChart.SeriesCollection(4).ErrorBar Direction:=xlY, Include:= _
xlPlusValues, Type:=xlCustom, Amount:="=MySheet!R2C17:R4C17"

When I try that code in 2007 I get error 1004, Application-defined or
object-defined error.