Known problems or limits regarding accessing BDB with Java via JNI

Hi,
we are currently in an evalutation phase and are planning to use BDB (C|JE) as back-end for a queueing system. This system is written in Java. One key requirement is high availability of the data hold in the back-end. We need the guarantee, that no data is lost, e.g. data added after checkpoints. The throughput is expected to be quite high (> 10.000.000 records hold within one single BDB-environment (we would use n parallel BDB-envs inside the service).
So i'm wondering about using JE or DB... The former doesn't provide a replication system but is a 100%-pure Java implementation, the latter is written in C and accessed via JNI, which adds some overhead and maybe instability issues but comes with an integrated replication system. JE would require us to develop an in-application replication system or to use a DFS for HA or something like that.
Are there any known issues regarding using DB with Java via JNI? Or any other hints?
TIA,
Dirk

Silly me, I forgot to mention that a null return value means that an exception was thrown so you should get that and print the value (although I suspect it will be "class not found").

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