my problem is which weblogic.jar is put in classpath of my third machine , i mean weblogic.jar of 6.0 or 5.1;whether i can use both??
I think you have a serious problem here.
You will be able to put only one of the files in the classpath. Even if you put both in the classpath only the first file will be referenced. My reasoning is that both contain files with a similar package structure and the file that you put first will be accessed and not the later file.
The only solution is to just go ahead and try putting the 6.0 version in the classpath and see if everything goes well.
But the jar file for 6.0 may not be backward compatible (dont know for sure) so there may be a chance that you application will crash some day on one particular operation.
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Mahindrakar
IBM Application Server & Developer Forum Moderator Consultant -
Zensar Technologies ,Pune India.
SCJP2, SCJD2 & SCJEA (Part I)