-Dlog4j.configuration jvm option didn't help

Also I noticed strange thing - even if I specify import:
org.apache.log4j;version="1.2.15", really used version is : lib/com.springsource.slf4j.org.apache.log4j-1.5.0.jar

1. How to configure log4j?
2. Is it possible to use platform logging capabilities from: com.springsource.platform.serviceability.* ?
I'm confused that those bundles don't export anything..

Olex