It is narrated from Sayyiduna Anas bin Malik (may Allah be pleased with him) that he said: "It was the people's practice that when the adhan was called for the Maghrib prayer, they would hurry to the pillars and pray two (voluntary) rak'ahs each, while the Messenger of Allah (peace and blessings be upon him) was present among them."
Imam al-Tabarani (may Allah have mercy on him) said: "No one narrated this hadith from Qatadah (may Allah have mercy on him), from Sayyiduna Anas (may Allah be pleased with him), except al-Hakam bin Hisham (may Allah have mercy on him)."