Mark Reinhold already stated on a few talks, including at JavaONE that Sun designed it that way on purpose as they wanted to keep everyone true to WORA without carrying native code around.

Which is also a reason why a replacement is being done as part of Project Panama, initially advocated by Charles Nutter due to the JRuby project issues.

http://openjdk.java.net/jeps/191

In alternative, if you have the source code available there is a way not to any transitions.

Java now has GraalVM and .NET had C++/CLI (nee Managed C++) since the beginning.