The latest service pack for Blackberry Enterprise Server 4.1, SP5, is having troubles after DST changes last night. CPU usage spikes to 100% and logs are filled with debug log entries related to threads.
The workaround so far involves decreasing the debug log level for the 6 services involved. You can read more about it at my post on Blackberry Forums

Who knows, maybe before its public launch on March 11, it will have also a HotFix release along with it. I’ll keep you all posted on