This one will be a bit easier than most, because it has been made known to you that this message is a telegram. Therefore, the plaintext ends with "end of message." Also, it probably contains at least one copy of the word-pair "full stop", which serves as a period or end-of-sentence marker.
A joint project of Prof. Seth Dutter and Prof. Gregory Bard of the University of Wisconsin---Stout, Department of Mathematics, Statistics, and Computer Science. (October 31, 2013)