Mobile devices have become ubiquitous, allowing the integration of new information from a large range of devices. However, the development of new applications requires a powerful framework which simplifies their construction. JXME is the JXTA implementation for mobile devices using J2ME, its main value being its simplicity when creating Peer-To-Peer (P2P) applications on limited devices. On that regard, an issue that is becoming very important in the recent times is being able to provide a security baseline to such applications. This paper analyzes the current state of security in JXME and proposes a simple security mechanism in order to protect JXME applications against a broad range of vulnerabilities.