MarkupBuilder: no such field "owner" error while generating HTML

This works in the Groovy Shell:

import groovy.xml.MarkupBuilder
doc = new MarkupBuilder()
doc.html() {
head()

}

But this fails:

import groovy.xml.MarkupBuilder

class HtmlMarkupSandbox
{
static void main(args)
{
doc = new MarkupBuilder()
doc.html() {
head()

}
}
}

With the following error:

java.lang.NoSuchFieldError: owner
at
org.codehaus.groovy.tools.HtmlMarkupSandbox$1.doCall(HtmlMarkupSandbox.groov
y)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39
)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl
.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at groovy.lang.MetaClass.doMethodInvoke(MetaClass.java:758)
at groovy.lang.MetaClass.invokeMethod(MetaClass.java:214)
at groovy.lang.MetaClass.invokeMethod(MetaClass.java:188)
at groovy.lang.Closure.invokeMethod(Closure.java:69)
at org.codehaus.groovy.runtime.Invoker.invokeMethod(Invoker.java:114)
at
org.codehaus.groovy.runtime.InvokerHelper.invokeMethod(InvokerHelper.java:92
)
at groovy.lang.Closure.call(Closure.java:145)
at groovy.lang.Closure.call(Closure.java:134)
at groovy.util.BuilderSupport.doInvokeMethod(BuilderSupport.java:129)
at groovy.util.BuilderSupport.invokeMethod(BuilderSupport.java:85)
at org.codehaus.groovy.runtime.Invoker.invokeMethod(Invoker.java:114)
at
org.codehaus.groovy.runtime.InvokerHelper.invokeMethod(InvokerHelper.java:92
)
at
org.codehaus.groovy.tools.HtmlMarkupSandbox.main(HtmlMarkupSandbox.groovy:9)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39
)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl
.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at groovy.lang.MetaClass.doMethodInvoke(MetaClass.java:758)
at groovy.lang.MetaClass.invokeStaticMethod(MetaClass.java:273)
at org.codehaus.groovy.runtime.Invoker.invokeMethod(Invoker.java:121)
at
org.codehaus.groovy.runtime.InvokerHelper.invokeMethod(InvokerHelper.java:92
)
at groovy.lang.GroovyShell.run(GroovyShell.java:171)
at groovy.lang.GroovyShell.main(GroovyShell.java:85)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39
)
at
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl
.java:25)
at java.lang.reflect.Method.invoke(Method.java:324)
at org.codehaus.classworlds.Launcher.launchStandard(Launcher.java:410)
at org.codehaus.classworlds.Launcher.launch(Launcher.java:344)
at org.codehaus.classworlds.Launcher.main(Launcher.java:474)