Traveler customers on Nokia 603, Nokia 700 and Nokia 701 who have upgraded their phones to Belle Feature Pack 2 will be blocked from syncing.. This problem was introduced by Nokia and they are working to resolve this issue asap. Here is the official statement from Nokia that can be provided to customers:

Nokia is working with IBM to resolve a software issue that prevents IBM Notes Traveler syncing with phones that have been updated to the latest Symbian Belle software update - Feature Pack 2. This affects the Nokia 603, Nokia 700, Nokia 701 and Nokia 808 PureView. Nokia and IBM are working to fix this issue and will provide an update as soon as one is available.
Belle upgrade to Feature Pack 2 is presently available as an over the air update. We recommend that enterprises using Notes Traveler inform their employees that, if using Nokia 603, Nokia 700, Nokia 701 and Nokia 808 PureView, they not upgrade the devices to Belle Feature Pack 2 at this time.