More informative error messages

Troubleshooting a Data Warehouse request--particularly when they take 10-12 hours to run--can be tough as it is.  Not having any information for request failures other than "has error" makes it nearly impossible.  It would help us to have some clarification (Omniture server error?  FTP error? Email size problem?) to at least the level of detail where we can figure out where the problem is and troubleshoot from there.