Need Help with log4J

[anilkumarkatta]

I'm using this log4j.properties file
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log4j.rootLogger=ALL, BEACON, stdout

# Write "Info"-level (and above) messages to a daily log file
log4j.appender.BEACON=org.apache.log4j.DailyRollingFileAppender
log4j.appender.BEACON.Threshold=info
log4j.appender.BEACON.File=E:/logs/application/beacon/beacon.log
log4j.appender.BEACON.DatePattern='.'yyyyMMdd'.txt'
log4j.appender.BEACON.layout=org.apache.log4j.PatternLayout
log4j.appender.BEACON.layout.ConversionPattern=%d %-5p %c - %m%n

# Write "Error"-level (and above) messages to Console
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Threshold=error
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d %-5p %c - %m%n
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its dailyrollingfileappender, it doen't creating a new file after a day, it simply overwritting the same file.. no log history is maintaind..