http://forums.aptana.com/viewtopic.php?t=7208:

This code:

<script runat="server">
Jaxer.response.setClientFramework(null);
Jaxer.response.headers["Content-Type"] = "text/html";
var h = Jaxer.response.headers;
var s = [];
s.length = 3926;
h['X-TEST-1'] = s;
</script>

runs fine. It just sets a header to a string of 3,925 commas. However, if you add:

h['X-TEST-2'] = s;

A second time, just before the closing script tag, I get a 500 from Apache, and this in my server error log:

[Mon Nov 10 21:08:43 2008] [warn] mod_jaxer: invalid data type (\x02) received, while expecting a body (4)
[Mon Nov 10 21:08:43 2008] [warn] [client 71.213.224.23] (500)Unknown error 500: mod_jaxer: parse response body failed

If I change 3926 to 3925, both headers get sent.

If I repeat this process for smaller lengths with more headers, I get the same error everytime it's around 7500-8000 total characters. Is there a limit to the total header length sent by Apache or Jaxer? I couldn't find anything by googling.

I found this while working on this: http://forums.aptana.com/viewtopic.php?p=26057

Davey said: "spoke with one of the server devs, and he said to open a ticket for the header length issue. It is a limit in the jaxer protocol, that we should be able to extend."