Got it! Sharing the solution with possible future desperados: this problem occurs when the HTTP protocol is downgraded to HTTP/1.0 (usually by an old proxy). Make sure you are able to enforce use of HTTP/1.1 and the fuzzy strings are gone …
Naveen, found solution for this? Just moved the WP 2.8 site to new host and suddenly with the same codebase, these seemingly random strings started appearing on some pages.
