then you need to backup your data frequently. Testing funambol ldap and caldav connector with my E65 makes me happy, but I always love to ensure never miss my data during tests.
So I saved my addressbook on memorycard (on linux I got no Nokia PC Suite) in that way:
1- go to addressbook, then Options > Select All
2- then Options > Copy > To Memory Card
Now you got your backup: let’s safely start our tests!