Apache Geronimo is rapidly maturing as an open-source application server and, in its 1.0 version, venturing outside the protected bounds of its previously out-of-view camp. But can Geronimo keep moving and slip past the well-guarded doors to the enterprise the way JBoss did?To answer that question, I'd like to know how eBay is using Geronimo. By its own account, eBay is using Geronimo in limited production settings. EBay gave a presentation that acknowledged as much at JavaOne to a late birds-of-a-feather session. I'd like to know more, but I didn't make it to the gathering, and eBay has otherwise covered its tracks. EBay doesn't want to talk about Geronimo until it's got more experience under its belt.

Nevertheless, Geronimo is on the move. It gained strength when IBM acquired the open-source software integrator, Gluecode, which included Geronimo in the stack. Once Gluecode was in the IBM corral getting blue-washed (transformed into an IBM-supported product), IBM became a contributor to the open-source project.

Another sign that Geronimo is on the prowl is Novell's endorsement. Novell was an early partner of JBoss when other companies refused to take JBoss seriously, and it shipped JBoss with its Suse Linux 9 in August 2004.

Suse 10 is due out soon, and when it ships it will include Geronimo, not JBoss.

"We think there are going to be two Java platforms: one will be JBoss, and the other will be Geronimo," said Justin Steinman, director of product management at Novell, and Novell's willingness to provide technical support for Geronimo may herald broader acceptance.

It's also a sign that Novell, after watching archrival Red Hat gobble up JBoss, can't stomach distributing JBoss anymore. The party line is that the change was made because "JBoss changed some of its license terms, which made it difficult to include JBoss," said Steinman. But it's also true that the application server is so central to other middleware that Novell needed to pull back and decide whether it was going to support Red Hat's middleware goals or its own. It's clearly decided to bet on the darker horse.

So Novell has switched horses, Geronimo is tracking JBoss, and it's possible we're watching the stealth arrival of the next $350 million piece of open-source software. (That's what Red Hat paid for JBoss in April.)

It's also possible that JBoss so dominates the enterprise already that Geronimo won't be able to fight its way in. I still think the range is open and that there's going to be more than one open-source horse in the race.