Problem with old-style abstract inheritance in grails 2.0

Old style abstract inheritance without creating db table for abstract class does not work in grails 2.0 as it described here: http://grails.org/doc/2.0.0/guide/gettingStarted.html#upgradingFromPreviousVersionsOfGrails.

I created abstract class in the src/groovy:

package testgorm

abstract class AbstractEntity

and domain class in grails-app/domain:

package testgorm

class Entity extends AbstractEntity {

String firstName;

static constraints = {
}
}

Application does not run with error:

Running Grails application

Caused by GrailsDomainException: Identity property not found, but required in domain class [testgorm.Entity]
->> 303 | innerRun in java.util.concurrent.FutureTask$Sync

• - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

  138	run in java.util.concurrent.FutureTask
  886	runTask in java.util.concurrent.ThreadPoolExecutor$Worker
  908	run in '' ^ 680	run . . in java.lang.Thread
  Error 2012-01-31 20:19:22,268 [Thread-10] ERROR context.GrailsContextLoader - Error executing bootstraps: Error creating bean with name 'pluginManager' defined in ServletContext resource [/WEB-INF/applicationContext.xml]: Invocation of init method failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsDomainException: Identity property not found, but required in domain class [testgorm.Entity] Message: Error creating bean with name 'pluginManager' defined in ServletContext resource [/WEB-INF/applicationContext.xml]: Invocation of init method failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsDomainException: Identity property not found, but required in domain class [testgorm.Entity] Line	Method ->> 303	innerRun in java.util.concurrent.FutureTask$Sync

• - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

  138	run in java.util.concurrent.FutureTask
  886	runTask in java.util.concurrent.ThreadPoolExecutor$Worker
  908	run in '' ^ 680	run . . in java.lang.Thread

Caused by GrailsDomainException: Identity property not found, but required in domain class [testgorm.Entity]
->> 303 | innerRun in java.util.concurrent.FutureTask$Sync

• - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

  138	run in java.util.concurrent.FutureTask
  886	runTask in java.util.concurrent.ThreadPoolExecutor$Worker
  908	run in '' ^ 680	run . . in java.lang.Thread

Process finished with exit code 1

Without inheritance from AbstractEntity in src/groovy all works fine.