http://www.slipstream.com/
AFAIK, that plugin needs to be obtained from your ISP, each version of Slipstream is made for a specific ISP and is particular to that service.

I have contacted them, and their response is that they don't make the plug ins that users do, Slipstream is all the same just re-packaged for each ISP. the working code is the same for all, just icons change

So then, has Slipstream updated their plugin yet? For Firefox 5 by now?

Please reread my answer, 'They" refers to slipstream technical support. (the actual company responsible for producing slipstream is: SlipStream Data Inc. and is a subsidiary of Research In Motion, the web address: http://www.slipstream.com and is administered by o1 communications o1.com). These are the companies I called (yes physically called along with hours of net research, I am not just another lazy ass looking for someone else to fix it for me) and was told that they DO NOT produce any plug ins For Firefox or any other browser, the plug ins are made by users of Mozilla products like Firefox. I hope this clears up what I am looking for, I would be happy to code it for others, but sadly I do not know even where to start. But I am sure that of all the talented individuals that have been part of the Mozilla development team someone could address this issue to help others. Thanks C. P.S. and if someone has not made one for ff4 I am betting that they haven't made on for ff5