XML configuration files parsing error?

Hi,
I got some errors when I launch either the proxy or IM client. It complains
configuration XML files has some problem. I attached IM client errors:
Buddies1.xml and Authentication.xml. The proxy error is the configuration.xml
file. However, it seems the values in those files can be retrieved still. Then,
what is the error about?

I use JDK/JRE 1.5.09 on Windows XP.

Thanks for any clue.

Buildfile: build.xml

run-im1:

     [java] ***************** STARTING ******************************

     [java] DebugIM, InstantMessagingGUI, we upload the properties from the 
file:.//configuration/gov/nist/sip/instantmessaging/configuration/im1.properties
     [java] DebugIM, InstantMessagingGUI, properties uploaded.
     [java] DebugIM, Parsing XML buddies
     [java] [Error] buddies1.xml:2:10: Document root element "BUDDIES", must 
match DOCTYPE root "null".
     [java] [Error] buddies1.xml:2:10: Document is invalid: no grammar found.
     [java] DebugIM, XML buddies parsed successfully!!!
     [java] DebugIM, BuddyList, init(), There are 2 buddies to upload.
     [java] DebugIM, BuddyList, init(), we uploaded sip:[email protected] to the 
buddy List.
     [java] DebugIM, BuddyList, init(), we uploaded sip:[email protected] to the 
buddy List.
     [java] DebugIM, XMLAuthenticationParser, startDocument():  Parsing XML 
passwords file
     [java] [Error] authentication.xml:2:17: Document root element 
"AUTHENTICATION", must match DOCTYPE root "null".
     [java] [Error] authentication.xml:2:17: Document is invalid: no grammar 
found.
     [java] DebugIM, XMLAuthenticationParser, endDocument():  XML passwords 
file parsed successfully!!!
     [java] DebugIM, the stack address is set to: 127.0.0.1
     [java] DebugIM, the outbound proxy is set to: 130.233.46.68:5060/udp
     [java] DebugIM, one listening point created: port:5060,  transport:udp
     [java] DebugIM, Instant Messaging user agent ready to work

     [java] *************************************************