Polls in side block triggering spam filter

I am having more than one user report to me that when they try to vote on a poll appearing in a side block, it will trigger the spam filter, and their vote is rejected.

Even with Mollom set up NOT to monitor polls, it still happens. It does not happen when people vote on the the poll which appears in the story content area (i.e. middle column in some themes), only in a side block.

Perhaps this is related to the Login problem reported elsewhere here.