Changing the Definition of a Week

Just curious if anyone has changed the definition of a week in Tessitura from Sunday through Saturday to something else.  Internally we've always defined a week as Monday through Sunday and would like to see Tessitura do the same specifically in the Campaign / Financial Summary tab.  I did figure out that I can add entry in T_DEFAULTS (EIS_FIRST_DAY_OF_WEEK) that will change it for the Ticket Sale By Period report, but it didn't seem to affect the Campaign summaries.  Any ideas?  Thanks!