We have got a multi-threaded enterprise application running on highly loaded 
weblogic server. We are getting this below error very frequently and causing 
our production server to go down. 

Pls see below Thread trace :

"ExecuteThread: '33' for queue: 'weblogic.kernel.Default'" daemon prio=5 
tid=0x30a8f0 nid=0x2d waiting for monitor entry [8fcfe000..8fd019bc]
	at org.apache.log4j.RollingFileAppender.rollOver
(RollingFileAppender.java:126)
	at org.apache.log4j.RollingFileAppender.subAppend
(RollingFileAppender.java:228)
	at org.apache.log4j.WriterAppender.append(WriterAppender.java:150)
	at org.apache.log4j.AppenderSkeleton.doAppend(AppenderSkeleton.java:221)
	- locked <b71560a8> (a org.apache.log4j.RollingFileAppender)
	at org.apache.log4j.helpers.AppenderAttachableImpl.appendLoopOnAppenders
(AppenderAttachableImpl.java:57)
	at org.apache.log4j.Category.callAppenders(Category.java:187)
	- locked <b715d2d0> (a org.apache.log4j.Logger)
	at org.apache.log4j.Category.forcedLog(Category.java:372)

Thread dump 1/4
" Thread-25402 <threadFilter.do?mode=ModeAllThreads&FullThreadIndex=0>" prio=5 
tid=0x14f92d0 nid=0x638b waiting for monitor entry [8a301000..8a3019bc]
    at org.apache.log4j.Category.callAppenders(Category.java:185)
    - waiting to lock <b715d2d0> (a org.apache.log4j.Logger)
    at org.apache.log4j.Category.forcedLog(Category.java:372)
    at org.apache.log4j.Category.log(Category.java:864)

Is there any know solution/patch for this error?

Thanks
Srinivas