Those drawbacks aside, Sapphire/Web has one of the best underlying server architectures we saw. The tested management features are strong, and access to back-end data sources, such as PeopleSoft and SAP, via SIM (Sapphire Integration Modules) is excellent.

Sapphire/Web's platform support is superb, with the server running under Windows NT, various versions of Unix (Digital Alpha, HP-UX, IBM AIX and SGI Irix), IBM OS/390, Digital Alpha Intel and others; Sapphire/Web is written completely in Java, so almost any platform with a compliant JVM (Java Virtual Machine) can be used, making it one of the few application servers available on mainframes. Native database access is provided for DB2, Informix, Microsoft SQL Server, Oracle and Sybase. Support for ADO (Active Data Objects), JDBC (Java Database Connectivity) and ODBC (Open Database Connectivity) is also available. The Visigenic Visibroker ORB (Object Request Broker) for Java is included, and IONA's Orbix and the Sun Java IDL (Interface Definition Language) are supported, for both CORBA (Common Object Request Broker Architecture) and EJB (Enterprise JavaBeans). Microsoft COM (Component Object Model) support is available, too, wrappered in Java.

Bluestone has provided good XML integration: Sapphire/Web uses a SIM to read XML, includes an XML content generator and bundles freeware XML parsers, putting it on the leading edge of XML support among application servers.

Although a high-performance stateless mode is available, we found the state/session management and object- caching features in Sapphire/Web very good. For example, it's one of only four products with true session-level failover (the others are WebObjects, IBM's WebSphere and SilverStream's Application Server), so we could interrupt Sapphire/ Web sessions and later reconnect without data loss. We gave a thumbs-up to the Java-based Admin Console, which allows remote performance and failure monitoring, and the granularity of control for the true dynamic load-balancing and failover features is among the best. The product supports SCCAPI; SIM support is available for transaction-processing systems.

Its power does exact a price, however. The development "starter pack," including five standard development seats, training, support and a development version of the application server, costs $25,000. Server pricing is determined according to three models: per CPU, at $20,000 each; unlimited site licensing, which is always negotiated; or a unique, tiered transactions-per-year license. The low end of the tiered license is $8,500 for 1 million transactions per year. Larger deployments can cost $40,000 to $50,000 for 10 million transactions per year, and licenses are available for up to billions of transactions.

Sapphire/Web's designers obviously paid a great deal of attention to the needs of enterprise developers and managers, and it is truly industrial-strength. The only notable drawbacks are its comparatively poor UI and IDE. But if you can develop your code with another IDE, you couldn't ask for a more full-featured, architecturally robust engine to drive mission-critical applications.