Oracle is Friday expected to start laying off at least 500 staff, eliminating duplication across product engineering and management, following its $8.5bn acquisition of BEA Systems.

Separate sources close to Oracle, who declined to be identified, said the company will send out notifications of layoffs tomorrow, and make a formal, public announcement next week..

Some business units will get hit hard, losing up to half their numbers, while others will escape untouched. Business unit managers have been given a head count by the Oracle chief financial officer's department and are making layoffs if they have more staff as a result of the merger.

It is not clear which units will feel the brunt of the cuts, or if Oracle engineering and business staff are also going.

It is understood that BEA's WebLogic Server unit is "safe". Oracle is believed to be updating WebLogic to support Oracle's business applications, and that - in doing so - has pushed back a summer update of WebLogic Server to later in the year.

This raises questions over the future of Oracle's application server and the status of the product's engineering team. Oracle has spent billions of dollars building and re-writing its application server. But in the end it turned to BEA, which was faster and had better ease-of-use features, to better close the gap with number-one IBM.

The companies also overlap in: portal - Oracle now owns four as a result of the acquisition; service oriented architecture; and development tools.

Oracle declined to comment.

Now we know why Oracle's server technologies development Thomas Kurian was so eager to skip over what Oracle had planned for BEA's WebLogic, AquaLogic and its own products during a JavaOne keynote (http://www.regdeveloper.co.uk/2008/05/08/oracle_kurian_bea_javaone/) presentation that was gloriously isolated from reality.®

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