Creating a servlet using scala in eclipse

Hi,
I am new to scala. just started learning scala. I just wanted to create a Hello world servlet using scala.

I just followed these steps.

1) created a dynamic web project
2) in the .project did the below mentioned changes. After which i got 'S' on the top of the project instead of 'J'
3) Created a scala class with the below code.
4) added the entry in web.xml.
But I am getting HTTP 500 ===> java.lang.ClassNotFoundException: HelloServlet

.project file

<?xml version="1.0" encoding="UTF-8"?>
<projectDescription>
	<name>scala-servlet-example</name>
	<comment></comment>
	<projects>
	</projects>
	<buildSpec>
		<buildCommand>
			<name>org.eclipse.wst.jsdt.core.javascriptValidator</name>
			<arguments>
			</arguments>
		</buildCommand>
		<buildCommand>
			<name>ch.epfl.lamp.sdt.core.scalabuilder</name>
			<arguments>
			</arguments>
		</buildCommand>
		<buildCommand>
			<name>org.eclipse.wst.common.project.facet.core.builder</name>
			<arguments>
			</arguments>
		</buildCommand>
		<buildCommand>
			<name>org.eclipse.wst.validation.validationbuilder</name>
			<arguments>
			</arguments>
		</buildCommand>
	</buildSpec>
	<natures>
		<nature>ch.epfl.lamp.sdt.core.scalanature</nature>
		<nature>org.eclipse.jem.workbench.JavaEMFNature</nature>
		<nature>org.eclipse.wst.common.modulecore.ModuleCoreNature</nature>
		<nature>org.eclipse.wst.common.project.facet.core.nature</nature>
		<nature>org.eclipse.jdt.core.javanature</nature>
		<nature>org.eclipse.wst.jsdt.core.jsNature</nature>
	</natures>
</projectDescription>

scala class

web.xml

index.html