I am thinking of getting an Eris, but am concerned about the calender. I am a therapist and need the calender not only to make reoccurring appointments, but I often need to change one of the occurances while keeping the rest in tact. Is this possible to do with the Eris? When I went to the Verizon store, they told me the calender wasn't taht sophisticated and that I should stick with my Blackberry. Thanks!