Microsoft has filed a counterclaim in the latest round of its courtroom battle with Sun Microsystems, accusing Sun of breaking contracts involving Java.
Sun's ongoing lawsuit alleges that Microsoft tried to crush its Java software.
But Microsoft has submitted a 51-page counterclaim which argues that Sun reneged on agreements which should have allowed Microsoft to distribute its own variation of Java through to 2008.
Microsoft said that a legal settlement in 2001 gave it the rights to produce its own Java Virtual Machine, but that Sun acted in "bad faith" and ended this licence.
In January Microsoft was ordered to start shipping Sun's Java program within 120 days as part of the court battle.
Sun is evaluating the counterclaim.
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