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+I have an [IkiWiki site](http://ocikbapps.uzh.ch/gc3wiki), which works
+fine, except for one page which I cannot edit with the CGI.  Only this
+single page is failing, editing every other works as expected.
+
+When clicking every button (well, except "Cancel") on the edit form, I
+get a "302 Found" page in the browser; the Apache logs show:
+
+    [client XXX] malformed header from script. Bad header=according%20to%20the%20availab: ikiwiki.cgi
+
+Capturing the output from `ikiwiki.cgi`, I see that just these two
+lines are sent:
+
+    Status: 302 Found
+    Location: https://ocikbapps.uzh.ch/gc3wiki/ikiwiki.auth.cgi?_submitted=1;do=edit;..;_submit=Preview;attachment=
+
+The total size in bytes of the reply is 16189; I thought this might be
+an issue with Apache imposing some limit on the header size; indeed,
+`tcpflow` shows that the "302 Found" message is encapsulated into an
+HTTP 500 "internal server error" response.
+
+So I added this to Apache's config (std Debian 6.0):
+
+    # cat /etc/apache2/conf.d/limits.conf
+    LimitRequestFieldSize 65534
+    LimitRequestLine 65534
+
+But I'm still getting the same error.
+
+Any suggestions?
+
+
+**Update 2011-08-16:** 
+[This bug report](https://bugzilla.mozilla.org/show_bug.cgi?id=513989) 
+shows the exact same symptoms; the solution they adopted is to not
+perform the redirect when the URL length exceeds the default Apache
+value of 8190.
+
+Regarding Apache limits: apparently, Apache (as of version 2.2.17)
+only applies the `LimitRequestLine` and `LimitRequestFiledsize` in
+client HTTP transactions; when dealing with the HTTP responses
+generated by CGI scripts, the code from `server/util_script.c`
+applies: (function `ap_scan_script_header_err_core`, lines 403--433)
+
+        char x[MAX_STRING_LEN];
+        char *w, *l;
+        [...]
+        if (buffer) {
+            *buffer = '\0';
+        }
+        w = buffer ? buffer : x;
+        [...]
+        while (1) {
+            int rv = (*getsfunc) (w, MAX_STRING_LEN - 1, getsfunc_data);
+
+where `MAX_STRING_LEN` is defined in `httpd.h` to be equal to
+`HUGE_STRING_LEN`, that is, 8192.
+
+> This has been filed as [[!debbug 638009]], so let's only
+> discuss it in one place (ie, there) --[[Joey]]