How about connection.getMetaData().getURL(), etc.?
If you can't call getMetaData() on the wrapped or pooled connection, maybe you can use JDK6's connection.unwrap() method to get to the underlying connection and get more info.
But I wonder why you got an exception from GlassFish. You obtained a datasource through injection or JNDI lookup? What exception did you get when you did what?
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