I would first suggest looking into what setting in Entourage is causing the data to be stripped. The idea here is to get a scope of the whole problem. Can a setting in Entourage be changed to fix this? Since Entourage is changing things, the first pass of fixes should come in Entourage.
If there is no solution within Entourage, then you need to find the filtering criterion causing your data be stripped and tweak the generated value for the key. Albeit, I would suggest getting a large public domain dictionary/word file ( http://www.google.com/search?num=50&q=public+domain+dictionary+file&btnG=Search )and using two or three random words put together as the new random key. Making the key too short will defeat the purpose of having it.