using mailto: body limit

I'm using the following code to fill an email for the user to send:

var t = escape(t); // to
var s = escape(s); // subject
var b = escape(b); // body

var doc = "mailto:"; + t + "?subject=" + s +"&body=" + b;
window.location = doc;

If works fine until the length of 'b' gets over about 255 character, then I get an "invalid syntax" error at the last line. Is there a limit on the size of the body text for an email in this case?

Andrew Poulos
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