The original Reuters story hit the wires with the line "Palestinian refugees in Lebanon... fled their homes after the creation of Israel in 1948." Not good enough for IRIN, part of the UN Office for the Coordination of Humanitarian Affairs. Their story, as fed through Reuters Alertnet:

Lebanon has the highest percentage of all Palestinian refugees living in abject poverty, according to the UN's Palestinian relief organisation, UNRWA. According to the AI report, disgraceful living conditions, continued restrictions on employment and lack of access to social services 60 years after their parents were driven from Palestine by the creation of the state of Israel, has left Lebanon's 400,000 officially registered refugees facing a daily struggle for survival.

Presumably they were using this map, which is all over the Internet:

Now without peeking at the answer, who can explain why this map is imbecilic? We understand there's a debate about whether a Palestinian people meaningfully exist (shared and distinct culture, shared and distinct history, etc). But surely we can all come together on the easily demonstrable historical fact that "Palestine" has never existed as a state and that the West Bank was part of Jordan and the Gaza Strip part of Egypt? Right?

References:
* Lebanon urged to treat Palestinian refugees better
* humanitarian news and analysis UN Office for the Coordination of Humanitarian Affairs
* LEBANON: End illegal discrimination against Palestinians, says Amnesty
* We have all been had

Previously:
* UN: Murder of Jews Not Really Our Problem
* UN Report On Security Fence Predictable In Every Way: Aggressively Contradictory, Blames Israel
* UN Ignores Palestinian Attacks Explicitly Designed To Target Israeli Schoolchildren