Config SLF4J using library to use LOG4J configuration - configuration

Question

I have a project using log4j. Now I have to introduce a library using slf4j. Can I ask slf4j to initialize itself based on log4j config? So I basicly want log4j as underlying library under slf4j.
UPDATE:
log4j config is like this:
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE log4j:configuration SYSTEM "log4j.dtd">
<log4j:configuration debug="true" xmlns:log4j="http://jakarta.apache.org/log4j/">
<appender name="fileAppender" class="org.apache.log4j.rolling.RollingFileAppender">
<param name="file" value="${log.dir}/${log.file}.log" />
<param name="append" value="true" />
<rollingPolicy class="org.apache.log4j.rolling.TimeBasedRollingPolicy">
<param name="FileNamePattern" value="${archive.log.dir}/${log.file}.%d{yyyy-MM-dd}.gz" />
<param name="ActiveFileName" value="${log.dir}/${log.file}.log"/>
</rollingPolicy>
<layout class="org.apache.log4j.EnhancedPatternLayout">
<param name="ConversionPattern" value="%d{yyMMdd HH:mm:ss,SSS} [%t] %-5p %c %X %m%n" />
</layout>
</appender>
<logger name="org.hibernate">
<level value="ALL" />
<appender-ref ref="fileAppender"/>
</logger>
<root>
<priority value="info" />
<appender-ref ref="fileAppender" />
</root>
</log4j:configuration>
I also use apache-log4j-extras version 1.0.
log4j version is 1.2.16

Answer 1

Yes, you need three jar files in your project's classpath:
slf4j-api-1.6.1.jar // the slf4j API
slf4j-log4j12-1.6.1.jar // log4j bindings for slf4j
log4j-1.2.15.jar // log4j itself
Make sure you have the same version of slf4j-api and slf4j-log4j12, otherwise it won't work. You can also use the newest log4j version, 1.2.16 if I'm not mistaken.