This is a follow on to the recent blog post about HttpClient .jar files. I'm writing because another vendor was using the Axis libraries we had in the classpath pre 3700.5.0. Those are gone too.
Always bundle all 3rd-party non-Blackboard .jars with your B2 and depend on those. Then the the B2 you ship won't break when Blackboard removes or upgrades the 3rd-party libraries in Learn that are/were on the classpath. And, be certain to keep the libraries your Building Block depends on up to date.
In general: Third party developers should include, and keep up-to-date, all non-Blackboard-authored jars that they need in their .war files, even if one that they need happens to exist in the class path already. Blackboard will be upgrading or removing these jars as required and without notice.