Hewlett-Packard Co. sued Oracle Corp. in a period of eight months showing a sign of how badly the relationship between the information technology big shots has ragged.

The lawsuit, filed on Wednesday in state court in San Jose, California, accuses Oracle of behaving illicitly in deciding that it would no longer support its database software to a particular line of HP servers that use the Itanium chip. Oracle also has used “strong-arm tactics” in forcing customers to “shift from HP’s Itanium server hardware to Oracle’s own server hardware,” the suit said.

The rivalry between the two companies started last year when Mark Hurd HP’s CEO was forced to resign and he wound up working as Oracle’s co-president. HP sued Hurd, alleging he couldn't do the job without divulging HP trade secrets. That lawsuit was later settled.

The current lawsuit involves an “Itanic” chip because it failed to transform the 'semi-conductor world' the way Intel and HP originally imagined.

HP machines still built on the chip have found some customers, and Oracle has worked closely with HP to make sure that its software is compatible, Bloomberg Businessweek reported.

Intel's plans to end-of-life Itanium will be revealed in court, now that HP has filed this utterly malicious and meritless lawsuit, Oracle said in a statement.

This case arises out of Oracle's failure to live up to a clear and simple promise to work with HP in the interests of both companies' mutual customers, HP said in the lawsuit. In a mere eight months, Oracle has gone from arm-in-arm 'partnership' with Hewlett-Packard to bitter antagonist.

Oracle said that its formal contract with HP does not include a guarantee of continued support for Itanium-based servers.

HP is seeking an order barring Oracle from pulling its support from Itanium computers.

It is unclear that the lawsuit might contain more serious allegations because many portions of the lawsuit are redacted.

Last week, HP warned Oracle that it would sue Oracle if it didn't quash its decision on Itanium. HP spokesman Bill Wohl said that the silence has been deafening from Oracle's lawyers since the letter.