Liferay : how to fix NoSuchBeanDefinitionException while portlet deploying

I would like to share the fix for mysterious and annoying issue that I've encountered during the development and deploying of a portlet for Liferay 5.2.3.

The error that Liferay server (Tomact) listed in the logs was related to misconfigured Spring beans and the exception was org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'my.service.persistence.SynergieCategoryPersistence.impl' is defined 
The partial stacktrace is belows:

16:36:12,700 ERROR [PortalClassLoaderServletContextListener:92] org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'my.service.SynergieCategoryLocalService.impl': Injection of BeanReference fields failed; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'my.service.persistence.SynergieCategoryPersistence.impl' is defined
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'fr.smile.synergie.service.SynergieCategoryLocalService.impl': Injection of BeanReference fields failed; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'my.service.persistence.SynergieCategoryPersistence.impl' is defined
 at com.liferay.portal.spring.annotation.BeanReferenceAnnotationBeanPostProcessor.postProcessAfterInstantiation(BeanReferenceAnnotationBeanPostProcessor.java:67)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:959)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:472)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory$1.run(AbstractAutowireCapableBeanFactory.java:409)
 at java.security.AccessController.doPrivileged(Native Method)
 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:380)
 at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:264)
 at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
 at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:261)
 at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:185)
 at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:164)
 at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:429)
 at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:728)
 at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:380)
 at org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:255)
 at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:199)
 at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:45)
 at com.liferay.portal.spring.context.PortletContextLoaderListener.contextInitialized(PortletContextLoaderListener.java:77)
 at com.liferay.portal.kernel.servlet.PortalClassLoaderServletContextListener.portalInit(PortalClassLoaderServletContextListener.java:89)
 at com.liferay.portal.kernel.util.PortalInitableUtil.init(PortalInitableUtil.java:47)
 at com.liferay.portal.kernel.servlet.PortalClassLoaderServletContextListener.contextInitialized(PortalClassLoaderServletContextListener.java:73)
 at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3843)
 at org.apache.catalina.core.StandardContext.start(StandardContext.java:4342)
 at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:791)
 at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:771)
 at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:525)
 at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:926)
 at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:889)
 at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:492)
 at org.apache.catalina.startup.HostConfig.check(HostConfig.java:1217)
 at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:293)
 at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:117)
 at org.apache.catalina.core.ContainerBase.backgroundProcess(ContainerBase.java:1337)
 at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1601)
 at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.processChildren(ContainerBase.java:1610)
 at org.apache.catalina.core.ContainerBase$ContainerBackgroundProcessor.run(ContainerBase.java:1590)
 at java.lang.Thread.run(Thread.java:680)
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No bean named 'my.service.persistence.SynergieCategoryPersistence.impl' is defined
 at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanDefinition(DefaultListableBeanFactory.java:387)
 at org.springframework.beans.factory.support.AbstractBeanFactory.getMergedLocalBeanDefinition(AbstractBeanFactory.java:971)
 at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:246)
 at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:185)
 at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:164)
 at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:880)
 at com.liferay.portal.bean.BeanLocatorImpl.locate(BeanLocatorImpl.java:59)
 at com.liferay.portal.kernel.bean.PortalBeanLocatorUtil.locate(PortalBeanLocatorUtil.java:58)
 at com.liferay.portal.spring.annotation.BeanReferenceElement.getResourceToInject(BeanReferenceElement.java:70)
 at org.springframework.beans.factory.annotation.InjectionMetadata$InjectedElement.inject(InjectionMetadata.java:180)
 at org.springframework.beans.factory.annotation.InjectionMetadata.injectFields(InjectionMetadata.java:105)
 at com.liferay.portal.spring.annotation.BeanReferenceAnnotationBeanPostProcessor.postProcessAfterInstantiation(BeanReferenceAnnotationBeanPostProcessor.java:64)
 ... 36 more

The portlet classes have been generated by build-service and the same code worked fine during last 2 years. So I was pretty sure that my Spring config is OK and the problem resides in the other part of the system.

After few days spent in debug mode, I have found that while deploying the portlet, the folder WEB-INF/lib was missing the jar file util-java.jar.
Obviously, util-java.jar is needed by Liferay to make some stuff. And apparently, in my case, this jar have not been copied automatically by Liferay hot deployer.

I have copied the missing util-java.jar to WEB-INF/lib and portlet has been deployed without any error.