NTT DoCoMo and Sun Microsystems have begun work on a new Java platform for cellular handsets. The work, which began last year but was first revealed two weeks ago at Sun's JavaOne conference in San Francisco, is aimed at refreshing the mobile Java platform for today's more advanced handsets and applications. It could also be promoted as a cross-industry standard, the companies said in interviews.

The work, which is taking place under the name Star project, has some ambitious targets. Chief among those is bringing DoCoMo's Java platform, which first appeared commercially in 2001, up to date, said Takeshi Natsuno, senior vice president of multimedia services at NTT DoCoMo.

"Star project is really targeting what Java will be for next-generation cell phones," he said.

Java is running on more than 700 million handsets worldwide, according to U.K. research company Ovum, but not all handsets run the same version. Despite its "write once, run anywhere" roots, Java is fractured in the cellular space because carriers and handset makers have all tweaked the technology to meet their needs. This means developers must often customize their Java applications, or "applets," for different handsets, creating extra work.

NTT DoCoMo's Java platform, called DoJa, is one of the most successful, thanks in part to the operator's lead in wireless Internet technologies. However, it is available only to DoCoMo and its handful of overseas partners. Other carrier-specific platforms exist, such as Vodafone Group's VFX and China United Telecommunications' (China Unicom) UniJa. Many other carriers use the MIDP (Mobile Information Device profile) platform, which has been standardized but can still differ from handset to handset.

"Both DoJa and MIDP have good points. The next Java should take advantage of both," Natsuno said. "But rather than combining DoJa and MIDP, we should be thinking from scratch. ... We're not intending to merge [them], but to take a reference from both sides and think about what should be the Java platform for future phones."

Bringing together the best of both worlds could be good news for developers, said Claus Hoefele, a Tokyo-based developer of Java for cell phones.

"DoJa is tightly embedded in i-mode and has a successful business model, while the strength of MIDP is in its openness and support from many manufacturers and operators," he said. "An advantage of DoJa is its stricter specifications and compliance tests, which reduce device fragmentation, a major complaint from software developers for MIDP. Combining the two worlds would definitely be a great idea."

"Different versions of the Java platform are a big problem," Hoefele said. "You have to create an application that is specifically written for your target platform. Supporting two platforms costs a lot of money, especially considering the short lifespan of a Java game."

Creating a new Java phone platform means having to examine where cellular handset technologies are heading. Natsuno wouldn't talk about DoCoMo's plans for future phones, but a look back at the four years since Java first appeared on cell phones shows how much technology has changed. Features that are standard for advanced phones in Japan today, such as contactless smart cards for making payments, digital music players, cameras and document-viewing software, were uncommon or unavailable in 2001.

So part of the Star project work is to consider the runtime environment in which the Java platform operates. Most phones today use the Connected Limited Device Configuration (CLDC), but some more advanced handsets such as those sold in Japan could benefit from the more capable Connected Device Configuration (CDC), Natsuno said.

CLDC's limitations are becoming apparent in some of today's powerful phones, but the technology is still fine for the vast majority of handsets, said Eric Chu, senior director of JavaME at Sun.

"If you chose the CDC solution, it's not right for 80 percent to 90 percent of the market. CLDC is the right platform, but on smart phones it is a little anemic," he said.

In working with DoCoMo, Sun isn't taking sides or promoting DoCoMo's platform over standards worked out jointly by carriers as part of the Java Community Process, said Chu. Rather, Sun sees it as an opportunity to work JCP-developed technology into DoCoMo's new Java platform, he said.

DoCoMo and Sun would not say how long it might take to develop the new platform, but Natsuno said the two years it took to develop DoJa could server as a guide.

The platform may be available for use by other carriers when it is complete, which could be a big boon for application developers.

"We are not intending to [restrict] this only for DoCoMo," Natsuno said.