I don't know if this post will be valuable or not, but let me tell you about it.
I am using Toplink as a JPA implementation on OAS from within Eclipse IDE, I am try to show the generated SQL by putting the following property in persistence.xml:
<property name="toplink.logging.level" value="FINE" />
It is supposed to work, but don't for me.
So, I find a workaround to find the generated SQL.
You will find the generated SQL here: "app_serv_home\j2ee\home\log\oc4j\log.xml"
Beware, the file is huge, so try to use a utility to tail the file for you (ex use GNU tail)