I have downloaded Hibernate, created a mapping file, and copied what I think (and README.txt indicated) is necessary to WEB-INF/lib of my webapp:

ant-1.6.2.jar
ant-antlr-1.6.2.jar
ant-junit-1.6.2.jar
ant-launcher-1.6.2.jar
antlr-2.7.4.jar
ant-swing-1.6.2.jar
cglib-full-2.0.2.jar
cleanimports.jar
commons-collections-2.1.1.jar
dom4j-1.5.2.jar
ehcache-1.1.jar
jaxen-1.1-beta-4.jar
jta.jar
versioncheck.jar
xml-apis.jar

I don't want to use Log4j and I don't have it in classpath, yet Hibernate ends up complaining as follows:
...
Caused by: java.lang.NoClassDefFoundError: org/apache/log4j/Logger
at org.hibernate.tuple.PojoTuplizer.<clinit>(PojoTuplizer.java:42)
...

This happens with Sysdeo's Tomcat plugin in Eclipse as well as when Tomcat is started as a service.

Could you make a hint what else should I check PLZ?

Maybe some log4j classes were found in one of the jars you used, so commons-logging considers it could be used, then it crashed when trying to load some other classes which were actually not present...

My 2 cents :-)

There are few in commons-logging.jar, but this is not probably what you mean. (The mentioned jar is required by Hibernate so it would be actually impossible to use it w/o Log4j.)

THNX anyways

I've made one more search in the forum and found several questions regarding the same problem, usually dated to 2005. So I ckecked the Hibernate package I downloaded before, and it seems to me that I "managed" to d/l some deprecated version of Hibernate (probably linked from one of the tutorials I took) that has just the problem.

I'm sorry for this

P.S.: Now another exception is thrown but it has nothing to do with logging and I'll play with it on monday, now gotta leave. :o)