1. Go to Connectivity > USB settings and set them to "Memory card"
2. Connect your phone with the computer with cable and go to /mobile/kjava
3. Copy the jar file there and disconnect the phone from the cable
4. Go to Java Apps and Games and choose Menu > Switch Storage Device > TFlash card
5. Press one up (so you go to the very bottom) and choose "Install New App"
6. Choose the app and follow the instructions (they are simple)
7. Go to USB settings under connectivity, switch to Data/Fax mode and read the next note
Note: Always use E1_FS to grant access when you install a java application. Do not post replies like "this application gives error when I try to load it", before you really run E1_FS. Download it here