Hi,
this just in from Proquest: 

ProQuest is performing a system maintenance to will improve performance and enhance Preliability.  The maintenance window will begin Wednesday May 3 at 11pm and end at midnight.

The following products will be unavailable during this brief window:
Please share this information with your colleagues.

Sherry

Sherry Willhite
Information Resources Analyst
CDL Information Services
California Digital Library