Uh. The code you post above seems like a total non-sequitor from what we were discussing earlier. I'm inferring that MT::PluginData::data is getting called from something in the above blob of code, but without grokking the entire system, I'm afraid I can't help you further.

If you have direct access to the database, you might try deleting the relevant rows (or entries out of the BerkeleyDB, etc) to see if it just random corruption. But without a lot more info about the system (which I simply don't have time to learn!), I don't have much else to suggest.

Good luck!