Back in August, Google acquired a Java/AJAX tool-developer called Instantiations. The company made a number of popular premium applications used by developers to help streamline production of their Java apps, particularly on Google Web Toolkit. And soon after the acquisition, Google rebranded and released these applications free of charge.

Today, Google is announcing that it’s doing itself one better: it’s open-sourcing most of the assets acquired in the deal, so that third parties can continue building out their feature-sets. The two donated projects are WindowBuilder, which is a Java GUI Designer for Eclipse, and CodePro Profiler, a tool that developers can use to discover memory leaks and other performance issues. Between the IP and code from the two projects, Google and the Eclipse Project estimate that this donation is worth over $5 million.

Google will be open sourcing the WindowBuilder layers for building apps on Swing and SWT — the layer for Google Web Toolkit, which is part of the Google plugin for Eclipse, will not be open-sourced (though they aren’t ruling this out for the future).WindowBuilder code will be maintained by the existing WindowBuilder team at Google, plus additional Google developers. CodePro Profiler will be maintained by a company called OnPositive.

One positive effect of this move is that third-party companies can now offer support services around these tools (something that Google has never focused on). Which means that enterprise businesses that want to take advantage of these tools will be able to pay someone for support. One company that’s setting out to do exactly this is Genuitec, which will offer support for WindowBuilder.