tomcat5.5+jdon3
2007-11-03 21:20:35,328 org.apache.commons.digester.Digester.error(Digester.java:1439) Parse Error at line 2 column 15: Document is invalid: no grammar found.
org.xml.sax.SAXParseException: Document is invalid: no grammar found.
....................
...................
2007-11-03 21:20:35,343 org.apache.commons.digester.Digester.error(Digester.java:1439) Parse Error at line 2 column 15: Document root element "struts-config", must match DOCTYPE root "null".
org.xml.sax.SAXParseException: Document root element "struts-config", must match DOCTYPE root "null".
启动是出现这种错误怎么解决?