appian 18.1 plugin development environment

Hi,

    I was trying to develop simple helloworld custom function plugin using eclipse Juno, jdk 1.8 and appain 18.1.   I placed the following jar files in the build path

 appian-plug-in-sdk.jar,

appian-suiteapi-18.1.23.0.jar

appian-logging-1.5.53.jar

I am getting following syntax error when i use annotations @AppianScriptingFunctionsCategory,@Category,@Function

Syntax error, annotations are only available if source level is 1.5 or greater

Do i need to switch my jdk from 1.8 to 1.5?  i was under impression that 18.1 plugin development api's are compatible with jdk 1.8

Here is my sample code 

package com.company.examples;

import com.appiancorp.suiteapi.expression.annotations.AppianScriptingFunctionsCategory;
import com.appiancorp.suiteapi.expression.annotations.Category;
import com.appiancorp.suiteapi.expression.annotations.Function;

@AppianScriptingFunctionsCategory
@Category
@Function
public class HelloWorld {

}

       Also is the any certified eclipse plugin available for development, the one available is not of much help for latest versions of appian. http://s3.amazonaws.com/appianplugins/eclipse/update/site.xml

Also with old version of appian , we are not able to create expression functions,smart services and data types in eclipse with this eclipse plugin.

     Can anyone please let me know what are the other jar files that need to be in build path apart from above listed jars?

Thanks