Not sure where they heard this "whisper" or if it has any truth to it, but here ya' go-
http://www.profootballweekly.com/PFW/The+Way+We+Hear+It/Whispers/2006/whispers2101.htm
"Why did the news that RB Ricky Williams had reportedly failed a drug test emanate from Denver? We hear it’s because the Broncos had requested information on Williams’ status in the NFL’s substance-abuse program from the league as a prelude to a trade with the Dolphins. Word is Williams’ appeal will be upheld since the substance he tested positive for was an herb, not a drug. However, the Dolphins are ticked off since the suspension scare likely lowers Williams’ trade value."
http://www.profootballweekly.com/PFW/The+Way+We+Hear+It/Whispers/2006/whispers2101.htm
"Why did the news that RB Ricky Williams had reportedly failed a drug test emanate from Denver? We hear it’s because the Broncos had requested information on Williams’ status in the NFL’s substance-abuse program from the league as a prelude to a trade with the Dolphins. Word is Williams’ appeal will be upheld since the substance he tested positive for was an herb, not a drug. However, the Dolphins are ticked off since the suspension scare likely lowers Williams’ trade value."