As one paragraph puts it;
"<I>Without a doubt, EPOC is an ideal OS for mobile handhelds. Even in its earliest incarnations, the software was designed with wireless functionality in mind, such as low-power consumption, and ARM-chip operability. Symbian's OS is a flexible, powerful platform designed to ride the transition from 2G to 2.5G and 3G and beyond, as well as provide a framework that supports everything from Java to WAP/XHTML. That's one reason the device makers didn't simply roll over and begin licensing Windows CE just to avoid sparring with Microsoft.</I>"
http//www.thefeature.com/index.jsp?url=article.jsp?pageid=14134