build identifier: m20090917-0800

if you design a joint data set in a .rptlibrary, and add a computed column in it, then export the joint dataset in a .rptdesign, the computed column won't be defined in the local version of the joint dataset.

reproducible: always
this looks work for me. can you attach the report?
i tried to reproduce it, but i couldn't. i can't see the difference with the previous situation. i close the bug until i meet it again.