Mailing List Archive

Intermittent "Request header field is missing ':' separator." on https

I'm trying to resolve a problem with intermittent "Bad Request" errors from

Bad Request

Your browser sent a request that this server could not understand.
Request header field is missing ':' separator.


Apache/2.2.14 (Ubuntu) Server at Port 443

These Bad Requests only happen with https (SSL cert from
Regular http doesn't show this problem. They are happening on both IE and

They showed up out of nowhere last friday (of course after I emailed a URL
to a client :-)

These "Bad Request" responses come back intermittently. I've checked that
the "good" requests are exactly the same as the "bad" ones with Firebug.
This is an example of a form POST, but it also happens on page GETs.

Here is an example of the request:
POST /index.php HTTP/1.1
User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:
Gecko/20100723 Ubuntu/10.04 (lucid) Firefox/3.6.8
Accept: text/javascript, text/html, application/xml, text/xml, */*
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 115
Connection: keep-alive
X-Requested-With: XMLHttpRequest
Content-Type: application/x-www-form-urlencoded; charset=UTF-8
Content-Length: 44
Cookie: secorix=i4dq7b23gcgf8trrprr6ieq5j5
Pragma: no-cache
Cache-Control: no-cache

The server is hosted by Amazon Web services, and is Ubuntu 10.04's standard
server distribution. $ dpkg -l '*apache*'
ii apache2
2.2.14-5ubuntu8 Apache HTTP Server metapackage
ii apache2-mpm-prefork
2.2.14-5ubuntu8 Apache HTTP Server -
traditional non-threaded model
ii apache2-threaded-dev
2.2.14-5ubuntu8 Apache development headers -
threaded MPM
ii apache2-utils
2.2.14-5ubuntu8 utility programs for
ii apache2.2-bin
2.2.14-5ubuntu8 Apache HTTP Server common
binary files
ii apache2.2-common
2.2.14-5ubuntu8 Apache HTTP Server common
ii libapache2-svn
1.6.6dfsg-2ubuntu1 Subversion server modules for

From the error log, I get these errors (intermixed with everything else):
[Mon Aug 30 21:27:06 2010] [warn] Init: Name-based SSL virtual hosts only
work for clients with TLS server name indication support (RFC 4366)
[Mon Aug 30 21:27:06 2010] [notice] Apache/2.2.14 (Ubuntu) DAV/2 SVN/1.6.6
PHP/5.3.2-1ubuntu4.2 with Suhosin-Patch mod_ssl/2.2.14 OpenSSL/0.9.8k
configured -- resuming normal operations
[Mon Aug 30 18:04:53 2010] [error] Hostname provided via SNI, but no
hostname provided in HTTP request
[Mon Aug 30 21:28:15 2010] [error] [client] request failed: error
reading the headers
[Mon Aug 30 21:53:42 2010] [error] [client] request failed: error
reading the headers, referer:

I've been searching forums all day but haven't found any fixes. Reset
browser cookies, and checked for proxies. Any advice?

Thanks in advance,