I have investigated some odd results I got when running Check/Synchronize on a customers test system. The conclusion was that SqlDictionary held wrong data, but I couldn't figure out why. My fear was that Check/Synchronize screwed up the data.
Today I found an article in the knowledge base describing that Check/Synchronize actually screws up the data in SqlDictionary.
The problem is "solved" in SP2 - by disabling the Check/Synchronize button.
Read more here.