Due to some odd circumstances, I updated a JBoss 3.2.(4/5/6) to 4.0.2, but was unable to run tests which used a MySQL JDBC resource.

I've recently run those tests, and while they used to work, I am now getting a NoClassDefFoundError on java.io.BufferedOutputStream from the MySQL driver.

I assumed this is some sort of classloader peculiarity, and I found a post in the wiki saying that DataSource drivers now had to be in server/default/lib rather than server/default/deploy, where my install had been putting it.

My question is whether this behavior change was intended, and if so, whether I should be doing anything else differently. When I set this up, the procedure was to put the driver JAR and the -ds file into server/default/deploy. Now, looking on the wiki under JCA, I find lots of references to RARs, and I'm wondering whether just moving the jar to lib will fix everything. When I did that, my JDBC accesses seemed to work OK, but I had tons of ApplicationDeadlockExceptions in the JBoss log.

Can I get a first-level opinion on this before I start posting diagnostic info ?

Thanks in advance,
Frank