I am new at ant I am trying a simple building with tomcat7, but the process stops with this error message

			

			BUILD FAILED
			

			/home/giuseppe/workspace/springapp/build.xml:82: taskdef class org.apache.catalina.ant.InstallTask cannot be found
			

			using the classloader AntClassLoader[/usr/local/tomcat/apache-tomcat-7.0.22/lib/catalina-ant.jar]
			

		

			

			<?xml version="1.0"?>
			

			

			

			

			

			

			

			

			

			

			

			

			

			

			
			

			
			

			
			

			

			

			

			

			

			

			

			

			

			

			

			

			

			Build the application"/>
			

			Deploy application as directory"/>
			

			Deploy application as a WAR file"/>
			

			Install application in Tomcat"/>
			

			Reload application in Tomcat"/>
			

			Start Tomcat application"/>
			

			Stop Tomcat application"/>
			

			List Tomcat applications"/>
			

			

			

			

			

			

			

			deprecation="false" optimize="false" failonerror="true">
			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			webxml="${web.dir}/WEB-INF/web.xml">
			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			

			username="${tomcat.manager.username}"
			

			password="${tomcat.manager.password}"
			

			path="/${name}"
			

			war="${name}"/>
			

			

			

			

			

			username="${tomcat.manager.username}"
			

			password="${tomcat.manager.password}"
			

			path="/${name}"/>
			

			

			

			

			

			username="${tomcat.manager.username}"
			

			password="${tomcat.manager.password}"
			

			path="/${name}"/>
			

			

			

			

			

			username="${tomcat.manager.username}"
			

			password="${tomcat.manager.password}"
			

			path="/${name}"/>
			

			

			

			

			

			username="${tomcat.manager.username}"
			

			password="${tomcat.manager.password}"/>
			

			

			

			
			

			

			

		

			

			# Ant properties for building the springapp
			

			

			appserver.home=/usr/local/tomcat/apache-tomcat-7.0.22
			

			# for Tomcat 5 use $appserver.home}/server/lib
			

			# for Tomcat 6 use $appserver.home}/lib
			

			appserver.lib=${appserver.home}/lib
			

			

			deploy.path=${appserver.home}/webapps
			

			

			tomcat.manager.url=http://localhost:8080/manager
			

			tomcat.manager.username=tomcat
			

			tomcat.manager.password=s3cret
			

		

I checked in the home of tomcat the jar is in the lib folder

can you help me to solve this problem? thanks in advance