启动tomcat总是在启动的日志里出现这三行警报，为什么？

启动tomcat总是在启动的日志里出现这三行警报，为什么？
2016-5-23 13:04:10,365 WARN [org.hibernate.internal.util.xml.DTDEntityResolver] - HHH000223: Recognized obsolete hibernate namespace http://hibernate.sourceforge.net/. Use namespace http://www.hibernate.org/dtd/ instead. Refer to Hibernate 3.6 Migration Guide!
2016-5-23 13:04:11,665 WARN [org.hibernate.cache.ehcache.AbstractEhcacheRegionFactory] - HHH020003: Could not find a specific ehcache configuration for cache named [org.hibernate.cache.spi.UpdateTimestampsCache]; using defaults.
2016-5-23 13:04:11,674 WARN [org.hibernate.cache.ehcache.AbstractEhcacheRegionFactory] - HHH020003: Could not find a specific ehcache configuration for cache named [org.hibernate.cache.internal.StandardQueryCache]; using defaults.