Looking on the mailing list [1] and on bugzilla [2] I got the info that log4j 1.2.x target JDK 1.1. The website [3] doesn't say something different.
However, when I look in the code, I see some usage of classes that only exists in 1.2 (HashMap and ThreadLocal for instance, and there is probably others). The usage of the targeting in the compilers is just completely broken, because the compiler just produce byte code in the targeting format, but doesn't check if you are using new classes/methods. It unfortunately doesn't check the 'since' tags of the methods (the Sun compiler at least). So, I'm afraid the target target 1.1 specified in the pom [4] should be changed (or you should find a 1.1 build environment, or at least a 1.1 test environment). [1] http://markmail.org/message/whsluupp4nub7hb3 [2] https://issues.apache.org/bugzilla/show_bug.cgi?id=42189#c18 [3] http://logging.apache.org/log4j/1.2/faq.html#1.3 [4] http://svn.apache.org/repos/asf/logging/log4j/trunk/pom.xml Gilles Scokart
