Copy chart between sheets

[Per <pmknutsen gmail com>]

Hi,
I have 20 identical sheet, each containing data obtaining in one
experiment. For one sheet, I have generated a chart with 10+ series
with error bars. When I copy this chart to another sheet, the data
sources are copied along with it. I want, however, the chart to use
the data in the same sheet (but same rows and columns).

How can I copy a chart but have Gnumeric 'forget' which sheet the
graph was copied from and instead use the data in the current sheet
only?

 - Per