Problem installing the IntelliJ plugin to RubyMine

I use RubyMine 1.0.5 and TeamCity Professional 4.5.1.

I downloaded the plugin IntelliJ IDEA plugin from "My Settings & Tools" and unzipped it to \config\plugins.
Then it is visible in Settings\Plugins but if i activate it, press apply und confirm the restart of the IDE it is not activated.

After the restart is remains disabled.

Any suggestions?

Thanks
Andreas