Although the OpenAjax Alliance was formed earlier this year, Sun opted not to join until now because the company had trouble understanding the goals of the group and was initially concerned about the group's close ties with the Eclipse Foundation, said Dan Roberts, Sun's director of marketing for developer tools.
Sun has been a high-profile holdout from Eclipse, which fosters open-source development tools.
"Initially there was the release of a set of tools around the Eclipse platform, and the [OpenAjax] site was hosted on Eclipse," Roberts said. "For us, if that was all they were doing, it wasn't very interesting. That they developed an Eclipse artifact is frankly a side activity to the alliance. The goals of OpenAjax are to be an independent community which isn't tied to any particular runtime or tool set."