Stuff I am about to try with EJBs

I am about to try out some things with EJBs in an 8.1.7 EE instance and thought I might ask around if anyone has already tested the following:
1. The EJB developers guide talks about a new database session being created whenever a client does a lookup on the InitialContext. If I use the same sid/user/password every time I look up an EJB, will I always be directed to the same DB session? Most importantly, if I have multiple web clients all referencing the same set of EJBs (e.g., CustomerEJB's), and I configure my app so that all EJB lookups use the same user/password, will the CustomerEJB instances be shared among all the client sessions?
2. What happens in an instantiated Entity EJB if the underlying table is updated via another mechanism (e.g., via SQLPlus)? Should I try to force a ejbLoad and ejbStore every time the EJB methods are used or does the Oracle RDBMS handle updating the EJB instances in memory?
Thanks,
John H.

I am making a sketchpad and when the user presses the arrow keys, it draws a line and stuff in the specified
direction. Is there a class that acts like a pen?Google for 'java etch-a-sketch' and you'll get lots of examples.

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