Talking to myself again here! Maybe it will help someone else. I just downloaded the jTDS driver (
http://jtds.sourceforge.net/) and it seems to work. I removed my persistence unit, and added a new one - went through the steps of adding a new DB connection, new driver etc. and then adding my entity class to the PU. Ran my same bit of code WITH the @Lob annotation present and it worked fine. I then wondered if I hadn't tried the SQL 2005 driver properly - so I went through exactly the same steps and it broke again.
I now have a bit of a dilema as to whether I should be using the jTDS driver. Time for more testing I guess, and a chat with my database chap!
I *think* this answers my question - but any further info on this would be useful.
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