Its a late replay but it may help someone..
I came across the same issue when using the log4j.
I use a property file file in src/main/resources/log4j.properties something like..
#
#------------------------------------------------------------------------------
#log4j.rootLogger=DEBUG, S, R
log4j.rootCategory=S, R
#log4j.logger.com.dappit.Dapper.parser=ERROR
#log4j.logger.org.w3c.tidy=FATAL
#------------------------------------------------------------------------------
#
# The following properties configure the console (stdout) appender.
# See
http://logging.apache.org/log4j/docs/api/index.html for details.
#
#------------------------------------------------------------------------------
log4j.appender.S = org.apache.log4j.ConsoleAppender
log4j.appender.S.layout = org.apache.log4j.PatternLayout
log4j.appender.S.layout.ConversionPattern =%d{yyyy-MM-dd HH:mm:ss} %t/%c{1} [%p] %m%n
#------------------------------------------------------------------------------
#
# The following properties configure the Daily Rolling File appender.
# See
http://logging.apache.org/log4j/docs/api/index.html for details.
#
#------------------------------------------------------------------------------
log4j.appender.R = org.apache.log4j.RollingFileAppender
log4j.appender.R.File = "DataSourceFactory.log"
log4j.appender.R.Append = true
log4j.appender.R.MaxFileSize=10MB
log4j.appender.R.MaxBackupIndex=1000
#log4j.appender.R.DatePattern = '.'yyy-MM-dd
log4j.appender.R.layout = org.apache.log4j.PatternLayout
log4j.appender.R.layout.ConversionPattern =%d{yyyy-MM-dd HH:mm:ss} %t/%c{1} [%p] %m%n
#---------------------------------------------------------------------------------------
removing the double quotes from the log4j.appender.R.File = "DataSourceFactory.log" entry solved my problem easily.