The recent development of software platforms for cell phones and handheld computers, such as Java 2 Micro Edition (J2ME), has broadened application perspectives in this area. The developers can now write their own software to run in handheld devices, what was impossible recently since the platforms were proprietary. Among the myriad of applications for these devices, some of them are very complex thus requiring the intelligent behavior typically provided by agents. However, since J2ME is a very recent platform, there are no well-established J2ME-based environments or tools for agent development yet. In this context, it is extremely helpful to develop building-block components, such as deductive inference mechanisms and communication languages and protocols. This paper describes the KSACI, a tool that provides communication infrastructure among agents running in handheld devices. KSACI supports KQML, as the outer language, and XML, as the inner one. KSACI extends SACI (Simple Agent Communication Infrastructure), a Java open-source communication infrastructure for desktop agents. Together with two other works presented in this book, KSACI represents a pioneer effort in the development of such communication tools. KSACI is already fully implemented and its preliminary test results on cell phone emulators are encouraging.