Error while starting jahia: NPE in JahiaFieldDefinitionsRegistry.loadAllDefinitions

Hi everybody,
 
I added a new virtual and removed another one and since then Jahia does not start up anymore.
A NullPointerException occurrs in the JahiaFieldDefinitionsRegistry.loadAllDefinitions method.
 
Any ideas on how to solve this?
 
(Jahia 5.0.0 running on ubuntu linux)
 
264843 [2006-11-15 15:15:17,688] [org.jahia.hibernate.manager.SpringContextSingleton] ERROR - Cannot load spring initialisation file
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.jahia.services.metadata.MetadataBaseService' defined in file [/opt/jahia5.0.0/tomcat/webapps/jahia/WEB-INF/etc/spring/applicationcontext-services.xml]: Can't resolve reference to bean 'JahiaFieldDefinitionsRegistry' while setting property 'fieldDefinitionsRegistry'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'JahiaFieldDefinitionsRegistry' defined in file [/opt/jahia5.0.0/tomcat/webapps/jahia/WEB-INF/etc/spring/applicationcontext-services.xml]: Initialization of bean failed; nested exception is java.lang.NullPointerException: null
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'JahiaFieldDefinitionsRegistry' defined in file [/opt/jahia5.0.0/tomcat/webapps/jahia/WEB-INF/etc/spring/applicationcontext-services.xml]: Initialization of bean failed; nested exception is java.lang.NullPointerException: null
java.lang.NullPointerException
        at org.jahia.registries.JahiaFieldDefinitionsRegistry.loadAllDefinitions(JahiaFieldDefinitionsRegistry.java:101)
        at org.jahia.registries.JahiaFieldDefinitionsRegistry.init(JahiaFieldDefinitionsRegistry.java:79)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:585)