"Since there was no response, our CEO Léo Apotheker took the initiative and wrote to both Oracle and Sun CEOs in the middle of September to voice our concerns again, offer a dialogue, and attempt to clarify the issues. We have not heard back from Oracle, but instead found Léo Apotheker's letter leaked to the press last week," the statement adds. "This is both telling and disappointing as it demonstrates that there is no real interest by Oracle to listen and explain how it wants to ensure the required level of customer choice in the database market as well as open access to Java."

In a blog post on Monday, SAP CTO Vishal Sikka also for more openness in Java.

Meanwhile, this week the European Commission issued a formal statement of objections to Oracle and Sun regarding the merger. The body is particularly concerned over the fate of Sun's open-source MySQL database if it comes under Oracle's ownership.

An Oracle spokeswoman declined comment.