At the upcoming ApacheCon in April, Bill Hilf and I will be presenting a talk called "Building a Large-Scale E-Commerce Site with Apache and mod_perl." One of the things we'll be covering is our use of Berkeley DB, including some problems we encountered with it and our recommendations on how to use it. If you're interested in using Berkeley DB, this might save you some trouble. (Stas, after the conference you might want to grab the info from our article in the conference handouts and add it to the Berkeley DB section of the Guide. Or I could do it and send it to you.) - Perrin