Encoded referral parameters

What are search engines telling me?

[eskwayrd]

I've noticed that a number of search engines that show up in my referral logs have URLs that have very long, encoded parameters. Most of these look like xargs=12KPjg1ttSr4Gm... (trimmed down from average 120+ bytes).

Some of the engines that do this are: alen.com, bestsearchonearth.com, browserdirect.net, cnn.com, exactsearch.net, overture.com.

Does anyone know what the encoding technique is? I'm really interested to know what the search engines are including in these parameters.

[flashfan]

The encoded one could be foreign language; like baidu.com.

[ronburk]

Despite periodic research on the subject, I know of no one who has decrypted the Overture xargs data and provided the results.