Hibernate ships with commons-collections-2.1.1.jar We are deploying it into WebSphere portal servers that come by default with commons-collections-3.0.jar, and this is now causing issues as we have need of the 3.0 features.

Can anyone tell us if there are any known incompatibilities between Hibernate and commons-collections-3.0? We currently use Hibernate 3.0.5 but I notice that even Hibernate 3.2.5 still uses commons-collections-2.1.1

Of course, there are workarounds for this, but your answer will help us to pick the best one.

Have you simply tried it? I think you will find v3 is largely backwards compatible.