KMail painfully slow... why?

While I've had no end of grief w/kmail2 after it switched to akonadi and have never been able to get search working, something else has popped up lately. Over the last two or three months, kmail2 has gotten *PAINFULLY* slow at doing just about anything. Click to switch from one message to another, and sometimes I can wait as long as 90s before the UI updates. Don't even get the "loading" screen, just waiting before it does anything. Only thing I've seemed to find that even helps at all is to log out and log back in again. Its then good for most of the day but by late afternoon things are bogging down again and I just close it and go back to logging in directly to my mail server and using "pine". Nepomuk is running, and is configured for e-mail indexing. Akonadi is running, but isn't complaining about any problems. When the problem occurs, its *not* CPU bound, so I'm pretty sure that its not the feeder/indexer hogging resources. Something, however, seems to be blocking and holding kmail2 up. Anyone got any suggestions? -- Graham TerMarsch