new File(System.getenv('HUDSON_HOME'), 'jobs').eachFile {j ->
    c = new File(j.absolutePath, 'config.xml')
    if (c.file) new XmlParser().parse(c).'**'.findAll{it.name() == 'mavenName'}.collect{"$j.name: ${it.text()}"}.unique().each {
  	 println it          
    }  
}

new File(System.getenv('HUDSON_HOME'), 'jobs').eachFile {j ->
    c = new File(j.absolutePath, 'config.xml')
    if (c.file) new XmlParser().parse(c).'**'.findAll{it.name() == 'mavenName'}.each {
  	 println "$j.name: ${it.text()}"          
    }  
}

new File(System.getenv('HUDSON_HOME'), 'jobs').eachFile {j ->
	c = new File(j.absolutePath, 'config.xml')
  	if (c.file) new XmlParser().parse(c).'**'.each {n ->   
  		if (n.name() == 'mavenName') println "$j.name: ${n.text()}"          
    }  
}

hudson_mvn_vers

Ant or JDK versions printing makes via the same way. Use 'antName' or 'jdk' instead 'mavenName' string.

Print maven version for all Hudson jobs

Groovy