When calling a Webi based on BEx query, with a input variable defined in the webi report(not in BEx query) on a characteristic with key and text available, pass the text value in lsSps<varname> and key value in lsIps<varname>
This became an issue when we updated BI Platform 4.0 from SP4 to SP6. We had a dashboard 4.0 application calling the webi report where the selected Business Unit in the dashboard was used to run the Webi report. The key value for Business Unit was being passed using URL parameter &lsSps<varname>=<var value> and it used to work in SP4. In SP6 we had to change it to &lsSps<varname>=<var value text> &lsIps<varname>=<var value key>