Yeah,
I tried to research this once, and it got in to the nitty gritty of DCOM permissions and mapi communications failures. There's a procedure you can go through to fix the dcom perm issues if they become a problem (ie, you start seeing eventlog errors), but Tony's right...if it's working, don't worry about it.
The most that it'll impact is client's tab and diagnostic readouts. Which is in a word...annoying.
micah