Set Email Description (body) with javascript

Question

I am trying to set the Email description in the OnLoad event of the email form in CRM 2011
Using this code:
"Xrm.Page.getAttribute("description").setValue(mailText.toString());"
In OnLoad of the email form my script is excecuted every time it loads / refreshes the page but the description is sometimes shown and sometimes not.
Does somebody know about this behavior and may have a solution?
Greez

Answer 1

Thx for your reply. The rest of the code is working. I debuged it about 1000 times. :)
But here it is:
function FillEmail()
var lookup = new Array();
regObj = Xrm.Page.getAttribute("regardingobjectid").getValue();
if (regObj != null)
if (regObj[0].entityType == "new_besuchsbericht")
var bericht = CrmRestKit.Retrieve("new_besuchsbericht", regObj[0].id, [
"new_name",
"OwnerId",
"new_OrtdesBesuchs",
"new_AnsprechpersonId",
"new_Besuchsdatumvon",
"new_Besuchsdatumbis",
"new_Teilnehmer",
"new_Beschreibung"
], null);
var thema = bericht.new_name;
var owner = bericht.OwnerId;
var ortDesBesuchs = bericht.new_OrtdesBesuchs;
var ansprechperson = bericht.new_AnsprechpersonId;
var besuchsdatumvon = bericht.new_Besuchsdatumvon;
var besuchsdatumbis = bericht.new_Besuchsdatumbis;
var teilnehmer = bericht.new_Teilnehmer;
var beschreibung = bericht.new_Beschreibung;
var ansprechName = "";
if (ansprechperson.Name != null)
ansprechName = ansprechperson.Name;
var dateVon = new Date(parseInt(besuchsdatumvon.replace("/Date(", "").replace(")/", ""), 10)).toLocaleString();
var dateBis = new Date(parseInt(besuchsdatumbis.replace("/Date(", "").replace(")/", ""), 10)).toLocaleString();
var mailText = "<div style=\"font-family: Arial; font-size: 11pt;\">";
mailText += "Thema: " + thema;
mailText += "<br/><br/>";
mailText += "Ort des Besuchs: " + ortDesBesuchs;
mailText += "<br/><br/>";
mailText += "Ansprechperson: " + ansprechName;
mailText += "<br/><br/>";
mailText += "Besuchsdatum von: " + dateVon;
mailText += "<br/>";
mailText += "Besuchsdatum bis: " + dateBis;
mailText += "<br/><br/>";
mailText += "Teilnehmer: " + teilnehmer;
mailText += "<br/><br/>";
mailText += "Beschreibung: <br/>";
mailText += beschreibung;
mailText += "</div>";
Xrm.Page.getAttribute("subject").setValue(thema);
var mailDescription = Xrm.Page.getAttribute("description");
if (mailDescription != null)
mailDescription.setValue(mailText.toString());
alert("description set");
The Subject is set every time and the "alert" in the end is fired after every load of the page.