WebPositive: Can't add comments/attachments in Trac

[bonefish]

hrev38606 gcc4

Trying to attach a file or add a comment with WebPositive results in the following error page being shown:

ERROR

The requested URL could not be retrieved

While trying to process the request:

POST /attachment/ticket/6530/?action=new&attachfilebutton=Attach+file HTTP/1.1
Host: dev.haiku-os.org
Accept-Encoding: deflate, gzip
Cookie: trac_auth=4a193a6f41cca4b33e67ec924bf6b3c1; trac_form_token=e97d2ae88abdd9aa342fe461
Origin: http://dev.haiku-os.org
User-Agent: Mozilla/5.0 (compatible; U; WebPositive/533.4; Haiku) AppleWebKit/533.4 (KHTML, like Gecko) Chrome/5.0.375.55 Safari/533.4
Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryFaaoWV5ynU5eUu73
Accept: application/xml,application/xhtml+xml,text/html;q=0.9,text/plain;q=0.8,image/png,*/*;q=0.5
Referer: http://dev.haiku-os.org/attachment/ticket/6530/?action=new&attachfilebutton=Attach+file
Content-Length: 8611
Expect: 100-continue

The following error was encountered:

Invalid Request
Some aspect of the HTTP Request is invalid. Possible problems:

Missing or unknown request method
Missing URL
Missing HTTP Identifier (HTTP/1.0)
Request is too large
Content-Length missing for POST or PUT requests
Illegal character in hostname; underscores are not allowed
Your cache administrator is admin@localhost. 
Generated Sun, 12 Sep 2010 10:25:39 GMT by proxy.centralhotelapart.de (squid)

If it wouldn't work fine with BezillaBrowser, I'd say something with the setup of the network I'm forced to use is incorrect.

[humdinger]

Since I comment and attach files to tickets here on Trac all the time... is this still valid?

[bonefish]

Replying to humdinger:

Since I comment and attach files to tickets here on Trac all the time... is this still valid?

I don't have access to that network anymore, but it sounds like the very recently reported #6848. Closing this one as a duplicate.