A quirk in the mail delivery system is forcing some residents of rural northern Missouri to have Iowa mailing addresses, causing problems when they vote, pay taxes and even when they die.

U.S. Sen. Claire McCaskill calls it "one of the dumbest things" she's seen and has sent a letter to Postmaster General Megan J. Brennan, asking that issue be resolved. The agency says it's working with the Missouri Democratic senator on the issue.

Local officials have been asking for help for years. In Missouri's Clark County, residents launched a petition drive this summer to get address changed because a new 911 system will need accurate addresses.

The Iowa addresses aren't recognized in Missouri's voting system. And some affected residents have been asked to file taxes in the wrong state.