Hewlett-Packard has agreed to buy Web application security specialist SPI Dynamics, just two weeks after IBM announced plans to buy SPI's rival Watchfire.

SPI, like Watchfire, develops software for finding vulnerabilities in Web applications, and for auditing their compliance with regulations on corporate governance such as the Sarbanes-Oxley Act.

HP plans to integrate the Atlanta-based company's business and its 140 staff into the software unit at its Technology Solutions Group, the business unit also responsible for servers, storage and consulting services.

SPI has been a partner and supplier to HP for some time, as Watchfire was to IBM.

The acquisitions leave one other player in the application security field adrift: Cenzic Inc. of Santa Clara, California, is a long-term partner of both IBM and Mercury Interactive, now a subsidiary of HP. Cenzic hopes to profit from the uncertainty in the market to gain share: it will offer up to six months free service for customers that trade in their Watchfire Appscan license for a subscription to its Hailstorm Enterprise ARC service, it said Monday.

HP expects to close the deal in the third quarter, subject to regulatory approval. The companies did not disclose financial details of the deal.