ical freezes when I try to add an event BUT only for 1 user

every time I try to add an event, I get the spinning wheel.

HOWEVER there are two users on this computer - when logged into the other account, ical works fine.

I have tried repairing permissions, deleting ical preferences, clearing out calendars, deleting sync services folder, even importing the database from the ical in the functioning user account.

all suggestions are extremely welcome at this point!

thanks very much
graham