The Apache Software Foundation is in a dispute with Sun Microsystems over a licence for the Java technology compatibility kit needed for the Apache Harmony project.
Harmony is an open source implementation of Java Platform, Standard Edition (Java SE) 5.
"We've converged on two different positions [regarding the matter] and there is a big gap," said Geir Magnusson Jr, vice president of the Java Community Process at Apache.
On 10 April, Apache posted online an open letter of protest to Sun signed by Magnusson.
"The JCK [Java Compatibility Kit] license Sun is offering imposes IP rights restrictions through limits on the 'field of use' available to users of our software," Magnusson said.
"These restrictions are totally unacceptable to us," he wrote. Sun could not be immediately reached for a response.
The restrictions are contrary to the terms of the Java Specification Participation Agreement (JSPA), to which Sun is bound, said Magnusson. Sun's JCK licence protects portions of Sun's commercial Java business at the expense of Apache's open software, he wrote.
"Such implicit or explicit threats of IP-based aggression give one actor overwhelming commercial advantages over the other participants in the ecosystem," said Magnusson in the letter. "In an open ecosystem, it must be the case that the necessary IP to implement a specification can be secured independently from the specific commercial interests of any one actor in the ecosystem, which is the basis of our objection to your offered terms."
Sun's terms hold back Harmony and pose credibility risks to the JCP and the reputation of Java as an open technology, according to the letter.
With its terms, Sun is attempting to circumvent a requirement that a specification lead not impose contractual conditions limiting the right of any licensee to build or distribute independent implementations. Sun must also license IP royalty-free, Magnusson said.
Apache is asking Sun to offer an acceptable JSPA within 30 days.
"The licence that Sun is offering us would put restrictions on how our users could use our independent implementation of Java," Magnusson said.
For example, if users wanted to use Harmony to power an information kiosk at an airport or use it in an X ray machine alongside Linux, they could not, "Sun considers that a use case that would be forbidden under the licence," Magnusson said.
Sun has not specifically asked for royalties, Magnusson said. From Apache's perspective, Apache could not distribute the software under an Apache license because the field of use limitation "prevents users from using the software as they see fit," Magnusson said.
"We worked very hard to avoid a public letter," he said. Apache has been seeking an acceptable license for testing Java SE since last August.
"It got to the point where we couldn't find anymore avenues of discussion,"
The Harmony project predated Sun's own open source efforts on Java, announced last November, by a year, Magnusson said.