Please, Mr. Postman! (OH!?ぷりーず♥みすたーぽすとまん, OH!? Purīzu ♥ Misutā Posutoman) is episode 177 of the original Naruto anime.
Naruto finds Jiraiya with two women in a town and Jiraiya makes excuses and puts off his training to write his Icha Icha script. Naruto eventually has to ghostwrite it. Naruto gets the manuscript for Icha Icha Violence mixed up with a peace treaty between the Land of Fangs and Land of Claws. The two must chase down the courier ninja before he delivers the wrong package and incites war. The courier however is absolutely committed to his duty and will stop at nothing to complete his delivery, no matter what the consequences may be. The wrong package eventually gets delivered but peace is still made between the two countries, as the recipient was a fan of Icha Icha and mercifully interpreted the document as a peace offering.