Did you ever get a solution to this? I'm seeing the same problem when attempting to bundle "vim25.jar" into my plugin.
Here is a list of steps to follow if you want to bundle vim25.jar with your plugin:
1. Remove any import packages of vim25 from the main bundle's MANIFEST.MF
2. Set the Bundle-Classpath to include vim25.jar (e.g. Bundle-Classpath: .,vim25.jar)
3. Include in the "Import-Package" of your bundle any packages that are imported by the vim25 bundle.