The agreement is between Microsoft and longtime rival Sun Microsystems. In the past, Microsoft has provided security fixes and other support for its version of Java, but Microsoft agreed to stop using the language as part of a 2001 court settlement.
The extension is to give those with programs in Microsoft's version of Java more time to switch to other programming technologies.
Microsoft's version of Java has long been a sore spot for Sun, which introduced Java in 1995 as a way for computer programmers to write applications that could run on any computer, regardless of operating system.
Microsoft bought a license for Java, then created and promoted an alternative version, which Sun contends effectively killed Java by removing its ability to work across different systems.
Sun sued Microsoft in 1997, leading to a 2001 settlement between the two companies that limited how long Microsoft could use Sun's Java source code.
Sun is continuing to press a $1 billion antitrust lawsuit against Microsoft for allegedly using anticompetitive tactics against Java. That suit is not affected by the agreement.
Microsoft has already stopped shipping its version of Java in its new products and is phasing it out of existing products, said Chris Jones, vice president for Microsoft's Windows Client division.