Oracle refused to provide critical bug fixes for customers who run its software on Hewlett-Packard's Integrity servers, in a bid to coerce them to switch over to Oracle hardware, HP alleged in a lawsuit it filed Wednesday.The accusation follows Oracle's decision in March to stop developing new versions of its software for Intel's high-end Itanium processor. HP's Integrity servers run on the Itanium chips, and the lawsuit accuses Oracle of violating legal commitments to HP in order to undermine the sale of its products."Oracle's sudden departure from its commitment of long-term support for the Itanium platform is a calculated effort to thwart competition from HP and harm its customers," HP said in the lawsuit, filed in the Superior Court in Santa Clara, California.HP had already complained that Oracle is harming the companies' joint customers in violation of its agreements with HP. Its lawsuit Wednesday describes in more detail what it sees as Oracle's "coercive" tactics.When Oracle announced its plan to end support for Itanium, it said it would continue to support customers running existing versions of its software on the Intel chip. Instead, according to HP, Oracle has refused to provide those customers with critical bug fixes for its software."Oracle has told customers that no fix is available and that to resolve the problem they will have to move to the next version of Oracle's software," the lawsuit said. "Because Oracle has announced that the next version of its software will not run on Itanium servers, this course of action by Oracle effectively forces customers to abandon their choice of Itanium servers in favor of server hardware they do not prefer."Oracle has also been offering to give away its server hardware away for free "to further sway and coerce customers" over to its products, HP says.The lawsuit escalates an ugly brawl between the companies that was triggered by Oracle's purchase of Sun Microsystems early last year, and which intensified when Oracle hired former HP CEO Mark Hurd, one month after he was forced to resign from HP.The lawsuit is heavily redacted to conceal the nature of the agreement Oracle allegedly violated, and some of HP's legal allegations are also blacked out. In those parts that are visible, HP is charging Oracle with breach of implied contract, defamatory libel and intentional interference with prospective economic advantage.An Oracle spokeswoman declined to comment on any specific allegations in the lawsuit. In a statement, Oracle denied any wrongdoing and accused HP of tricking it into signing an agreement last September to continue its support for Itanium, even though HP knew at the time that Intel planned to stop developing Itanium. "We believe that HP specifically asked Oracle to guarantee long-term support for Itanium in the September of 2010 agreement because HP already knew all about Intel's plans to discontinue Itanium, and HP was concerned about what would happen when Oracle found out about that plan," Oracle said.Intel hasn't announced any plans to discontinue Itanium, and both HP and Intel insist they are committed to keep developing the chip. Intel spokeswoman Kari Aakre reiterated Wednesday that Intel plans to deliver at least two more generations of Itanium, known as Poulson and Kittson. Still, Oracle said on Wednesday that "Intel's plans to end-of-life Itanium will be revealed in court."It's not clear from HP's heavily-redacted lawsuit what agreement Oracle is alleged to have violated. A spokesman at HP declined to provide any additional comment. Some of the remedies HP is seeking are also blacked out. The company wants the court to reverse Oracle's decision over Itanium, prevent it from making "false and misleading statements" about Itanium, and pay treble damages, including punitive damages, the lawsuit said.