artist,
As far as I can tell, this message is coming from DBI. You likely have a missing:

$sth->finish;
[download]

I am betting that the problem is not in either module but with your code. Feel free to share that since my crystal ball is in the shop.?

Update: Now that you have added some code, it appears that DESTROY calls STORE('Active', 0) which is apparently failing. STORE() is inherited from DBD::File which passes it up to DBI. I do not know why this appears to be failing but it might help jZed in tracking it down. I also figured out through experimentation that the error doesn't happen if you don't actually execute the statement handle (i.e. access the file). Save extremely drastic measures, I am not sure how you would disable this warning.