Check the JAD file.

Make sure the MIDlet-Jar-Size property matches the actual size of the JAR file.

To check the actual size of the JAR file, you can use Window's file properties dialog. From Windows Explorer, right click on the JAR icon. From the pop-up menu, choose "P[u:f9d962644c]r[/u:f9d962644c]operties". Windows will report two sizes. One is the "Size on disk" which you don't care about. The other is simply "Size" and it must match exactly with the value in the JAD file next to "MIDlet-Jar-Size". Don't use commas in the JAD. Just enter the number of bytes.

You shouldn't need to adjust the MIDlet-Jar-Size property at all. The Sprint Wireless Toolkit should have generated the JAD file with the proper size automatically. If there is a size mismatch then there is probably some other mismatch as well.