Why LogManager load log4j.properties from target/test-classes when run TestNG in Eclipse

[Bruce Wen]

Hi All,
I am wondering how classpath is decided when run TestNG suite xml file in 
Eclipse. Why it add target/test-classes in classpath and LogManager load 
log4j.properties from there rather than target/classes folder.
I hope somebody can help clarify the root reason for that. Thanks!
Bruce Wen