Mujibur Rahman (not the deceased prime minister of Bangladesh) and Sirajul Islam worked at K&L's Rock America gift shop, which neighbored the CBS studio where The Late Show with David Letterman is taped. As with many of Letterman's nearby shopkeepers, the show's writers started including the two men in various occasional skits, beginning with an appearance on September 13, 1993.
When it was clear that the polite, grinning immigrants had really clicked with the The Late Show audience, Mujibur and Sirajul were elevated from mere foils for Letterman's gags into official representatives of the show, and were sent around the country in 1994 as roving ambassadors of goodwill, supposedly at Letterman's behest. During this tour, the pair almost always wore the same suit-and-tie outfits they wore back at the gift shop, even if Letterman had them fly fishing in Montana or riding into the Grand Canyon on a couple of donkeys. Every time, suits and ties, every time the same singsong "Hello Daaaaave". The audience loved it.
After nearly a decade of Mujibur-enhanced television, the magic came to an end in January 2003, when the K&L gift shop decided to go out of business due to increasing rent costs. Letterman delivered the sad news to his audience and presented Mujibur and Sirajul with roses and a couple of vacuum cleaners, but suprisingly, no ham.
Mujibur and Sirajul have been friends ever since they attended the University of Dhaka together in India. Their show business careers are managed by Big Look Management, who also manage Yasmine Bleeth, Calvert DeForest, and the CBS Late Show Band, among others.