By Arnaud Zajtman
BBC News, Kinshasa
A group of disabled Congolese musicians is threatening to take the United Nations peacekeeping mission to court over a song for last year's elections.
The group are demanding $100,000
Let's Go and Vote was played repeatedly in the run-up to last year's historic polls on radio and TV stations.
In a country where a third of the population is illiterate and with crumbling infrastructure, the song is credited with boosting turn-out to 70%.
But the eight members of the Staff Benda Bilili band were paid $50 each.
The UN has denied any responsibility for paying royalties.
On the video clip that became a hit, the street musicians appeared in their wheelchairs, dancing the rumba and urging people to "go and vote" for a brighter future in DR Congo.
"It is thanks to our song that people went and voted but Monuc [UN Mission in DR Congo] did not pay us and we are still forced to sleep and beg in the streets. This is slavery," said band leader Nzale Makembo.
Most of the band are polio victims, who sleep rough next to the barbed wire fence which surrounds the Monuc headquarters in Kinshasa's dirty city centre.
The musicians were not offered contracts, but the credits on the video clip says it was produced by Monuc and distributed by the UN Development Programme (UNDP).
Despite their lack of financial resources, the musicians have engaged a lawyer who has lodged a formal complaint with Monuc's litigation department and is threatening to sue Monuc.
"The musicians deserve their royalties and Monuc has failed to pay them. This is piracy and fraud," said their lawyer Ali Ahoka Omeonga.
DR Congo has a long established music tradition and the law says that authors have an "inalienable right" to their copyright. However, UNDP spokesman Francois Charlier acknowledged that no royalties were paid to the musicians.
Monuc information chief Mario Zamorano confirmed the involvement of his organisation but said it only brought "technical support" and had therefore no responsibility to pay royalties.
In a letter to the musicians' lawyer, Danier Bart of Monuc's litigation department said the complaint could not be looked into, since the video clip was "not a sufficient piece of evidence" that the musicians had been employed by Monuc.
Monuc was closely involved in organising last year's poll - the first free election in more than 40 years.
It has an annual budget of more than $1bn.
The musicians are claiming $100,000 from Monuc as compensation for their copyright.
"Of course, this might seem a lot of money, but it is for Monuc to come and negotiate," said Mr Makembo.
DR Congo is slowly emerging from decades of conflict and mismanagement and the judiciary is still largely seen as dysfunctional.
Mr Makembo says he hopes "a legitimate organisation" like Monuc will eventually recognise the musicians' rights and comply to the rule of law.
But so far, Monuc, seen as one of DR Congo's most powerful organisations, has refused to open negotiations with the polio victims of Staff Benda Bilili.