Reporting services

Hi all,
I have three data sets to populate a report. and after this I have to use these datasets in an expression but they cause these errors which says that the report item needs to be in the same scope as the dataset and that it cannot be used in an aggregate function. Can we use multiple dataset in an expression inside the a report if so how? (p.s one of the datasets is a stored proc) what this sproc does is that it give a header name for my report headers. the others r used to populate the detail row by comparing it with the sproc as well as the other dataset.

any ideas?
thanks

Forum for reporting services:

http://forums.microsoft.com/MSDN/ShowForum.aspx?ForumID=82&SiteID=1

Thanks