The Sunnah regarding the Du`a' for a dead person after burying him

Q 4, 5: What is the Sunnah (action following the teachings of the Prophet) regarding the Du`a' (supplication) for a dead person after burying him? People usually surround the grave after burying the dead person, so, should they be facing the Qiblah (Ka`bah-direction faced in Prayer) when making Du`a' for the dead or is nothing wrong with making Du`a' regardless of the direction that one is facing? Is there a specific Du`a' for such a situation? What is the ruling on staying after burying the dead person to receive consolations from those who attended the funeral? If someone attended a funeral and the dead person's family stood after his burial, should one offer them his consolations or should he go and leave them?

A 4, 5: What was reported from the Prophet (peace be upon him) is a general command to make Istighfar (seeking forgiveness from Allah) and Du`a' for the dead person. It was narrated on the authority of `Uthman (may Allah be pleased with him) that he said: Whenever Allah's Messenger (peace be upon him) finished burying the dead, he used to stay with him (i.e. at his grave) and say: Seek forgiveness for your brother and steadfastness for him, for he is being questioned now. This was narrated by Abu Dawud and Al-Hakim, who considered it a Sahih (authentic) Hadith. Hence, one should say: O Allah, forgive him, keep him steadfast on the truth and keep him firm with the word that stands firm...Etc. It is not a must to face the Qiblah when making Du`a' for the dead person after burying him, rather one can make Du`a' regardless of the direction he is facing.