A group of open source companies from a variety of different product areas has banded together in an effort to improve interoperability among their products.

The Open Source Alliance is the latest effort by open source companies to team up in an effort to compete with their more established counterparts in the proprietary software world. Initial members of the organisation, announced at the Open Solutions Summit in New York, include Adaptive Planning, Centric CRM, CollabNet, EnterpriseDB, Hyperic, JasperSoft, Openbravo, SourceForge.net, SpikeSource and Talend.

Notable by their absence, however, are any large Linux platform vendors. Indeed, Red Hat on the same day announced it would join Microsoft's Interop Vendor Alliance in order to ensure its JBoss middleware continues to work well with Windows.

Other significant open source players missing from the group include MySQL, SugarCRM, Alfresco and XenSource, some of whom, like XenSource and SugarCRM, are part of the Interop Vendor Alliance.

The OSA's formation follows the recent merger of the Open Source Development Labs and the Free Strandards Group, forming the Linux Foundation.

The OSA is different from any existing group in that it's technology-neutral and open to all, according to Centric CRM chief marketing officer Michael Harvey. He pointed out the breadth of the initial members' products, which include databases, systems management, business intelligence, enterprise resource planning, customer relationship management and other offerings.

He said the group started off with smaller members but is open to bigger companies, including proprietary vendors - up to and including Microsoft. The focus is targeting business customers who want to be able to easily use disparate products together.

Goals include single sign-on, common license management and shared customer account records, Harvey said. The group isn't intending to set standards but to look at practical ways of implementing such features.

Separately, OS member SpikeSource said it had added more software to the products it tests and distributes, adding network management software from Hyperic and instant messaging from Jive. SpikeSource said it would begin distributing product stacks for Ubuntu Linux in the second quarter.

SpikeSource certifies stacks of open source components, testing that they work well with one another and with particular platforms, and providing automated updates and support. The company works through a network of resellers.