I have installed netbeans+jdk7u6 bundle from oracle site and jdk7 is referred only by netbeans and my system has openjdk6 which i use for writing & compiling programs from command line.
If i am not wrong java ee 6 is just a spec and implementations are GlassFish AS , tomcat etc.
does installing tomcat(of course the version supported by my netbeans version) alleviate my problem?
を使用して、NetbeansでJavaプラットフォームを管理できますTools -> java platforms。Javaプラットフォームを管理（追加または削除）し、NetBeansにどちらを使用するかを指示するだけです。right clicking on project -> properties -> compile
Not shure what NB version is bundled by oracle, but there's a Java EE package of Netbeans: http://netbeans.org/downloads/index.html (Java EE)
If you don't have this one (or the 'all') you can install it via Tools -> Plugins -> (Available Plugins) and select eg. Jave EE Base or whatever you need.