appending e mail identification data into {HEAD ~ a header} of {TAIL ~ the mail thread} of the at least two e mail messages when transmitted, wherein the e mail identification data includes at least: 
of
appending e mail identification data into { HEAD ~ a header } of { TAIL ~ the mail thread } of the at least two e mail messages when transmitted , wherein the e mail identification data includes at least :
OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH