Here some info regarding Lake Tanganyike (location of blocks 5 & 6).  These licenses must of been recently issued as most articles states that no licenses have been issued to date on the congo side of the lake. Total's licenses are on the Tanzania side of the lake.
The area of greatest interest for oil exploration in Lake Tanganyika is probably on the Congolese side. “There is an oil slick, a natural oil seep, that sits on the lake on the DRC side.  You can actually see it on Google Earth.  I think it’s the largest natural oil seep in the world.  What that indicates is there’s a working petroleum system underneath the Lake,” said Jamieson.
Unlike Tanzania and Burundi, the Democratic Republic of Congo has not issued any exploration licenses for Lake Tanganyika.  In 2008 the DRC government signed a joint exploration deal with Tanzania but according to the International Crisis Group, a policy think tank, this agreement was never implemented.
Last year the Tanzanian Petroleum Development Corporation asked permission for Beach Energy to enter the Congolese side of the lake to facilitate its exploration on the Tanzanian side.  According to a diplomatic source this request has not yet been granted, but the DRC government has asked for the request to be resubmitted.
Beach Energy said getting that permission from the DRC  had been an issue for the company, but it was possible to carry out its survey without entering Congolese waters.
DAR ES SALAAM (Reuters) - French oil major Total is close to signing a deal to explore for oil and gas in Tanzania's Lake Tanganyika, a senior Tanzanian petroleum official said on Thursday.
Total won a bidding round against eight other companies in August 2011 to explore the block but has been unable to do any work in the area while it discussed terms of a production sharing agreement (PSA) with the government.
"Total is in the very late stages of negotiation," Meshack Kagya, senior principal petroleum geochemist at the state-run Tanzania Petroleum Development Corp., told a gas conference.
Tanzania, east Africa's second-biggest economy, became a player in energy this year with several onshore and offshore gas finds, attracting multinational explorers to the area.
The country reportedly has about 30 trillion cubic feet of gas, which could make it a major energy exporter.
Total's PSA application is one of six the government is currently processing for companies. Two PSAs are for onshore blocks, and the others are for deep sea exploration spots.
Lake Tanganyika, where Total's new exploration area lies, sits on the western border of Tanzania and the eastern border of the Democratic Republic of the Congo.
Bodies of water that sit on onshore borders have been notoriously hard to explore as disputes over who owns the resources beneath lakes and rivers often erupt between countries.
In July, Tanzanian authorities asked UK explorer Surestream Petroleum, which Malawi authorities had licensed, to stop drilling on Lake Malawi. That dispute is ongoing.
Kagya said Tanzania was hoping to make more exploration blocks available soon, though he acknowledged it would take time. A licensing round that was supposed to take place in Houston, Texas this month was delayed and will be rescheduled in the near future.
"It has been delayed for some technical and housekeeping reasons," he said.
Lake Tanganyika 
Lake Tanganyika is a new oil exploration area shared by 
four countries: DRC, Zambia, Burundi and Tanzania. Only 
the latter two countries have issued exploration licences. 
Tanzania has allocated the southern block to the Australian company Beach Energy and its Tanzanian subsidiary Beach Petroleum Tanzania in 2008, and the northern block 
to Total in 2011. 100  Burundi has granted Surestream a licence for blocks D and B, 101  A-Z Petroleum for block A and Minergy Ree for block C. 102
In 2008, the Congolese hydrocarbons ministry divided the 
country’s share of the lake into ten blocks. However, this 
division is not yet official. The lake is not currently a focus of major problems, but the Ruzizi River delta was 
disputed in the 1980s.