jre uninstaller does not remove dlls from mozilla/plugins directory

Tested Build : mustang jre build 59d
Tested OS : windows

1. Install mustang jre build 59d
2. go to mozilla.org/plugins directory
3. Make sure that np*.dlls available (npjava11.dll, npjava12.dll, npjava13.dll, npjava14.dll,npjava32.dll,npjpoi160.dll,npoji610.dll)under plugins directory
4. uninstall mustang jre build 59d
the dlls are still available in the plugins directory

Expected behavior : these dlls should be removed