The following are quote from Sina's Challenge. I found this website accidentally while arguing with somebody about the term 'pedophile' and 'paedophile'.

Muhammad: A Pedophile 

Muhammad “married” Aisha when she was six years old.

'A'isha (Allah be pleased with her) reported: Allah's Apostle (may peace be upon him) married me when I was six years old, and I was admitted to his house when I was nine years old. Muslim 8. 3310

Narrated 'Aisha:that the Prophet married her when she was six years old and he consummated his marriage when she was nine years old, and then she remained with him for nine years (i.e., till his death). Bukhari 7. 62. 64

Narrated 'Aisha:that the Prophet married her when she was six years old and he consummated his marriage when she was nine years old. Hisham said: I have been informed that 'Aisha remained with the Prophet for nine years (i.e. till his death)." what you know of the Quran (by heart)' Bukhari 7. 62. 65

Narrated 'Ursa:The Prophet wrote the (marriage contract) with 'Aisha while she was six years old and consummated his marriage with her while she was nine years old and she remained with him for nine years (i.e. till his death).Bukhari 7. 62. 88

Arab year is lunar, which is shorter than solar year. In solar years, Aisha was 8 years 9 months old when Muhammad consummated his marriage with her. Consummate? This is a nice way to say raped her.  According to Muslims, a woman must consent to her marriage or the marriage is null.  How can a 6-years old child consent to her marriage?  Without a consent, how can we call this relationship between a 51 years old man and a  6-years old child marriage?

Some Muslims claim that it was Abu Bakr who approached Muhammad asking him to marry his daughter. This is not true.

The Prophet asked Abu Bakr for 'Aisha's hand in marriage. Abu Bakr said "But I am your brother." The Prophet said, "You are my brother in Allah's religion and His Book, but she (Aisha) is lawful for me to marry." Bukhari 7.62.18

Even though Abu Bakr was fool enough to let Muhammad have sex with his little daughter, that marriage was invaled, because the only person who should have given consent was a minor.  Aisha was unaware of what was going on and was surprised when Muhammad pulled down his pants and invited her to sit on his lap. SheNarrated:

When the Prophet married me, my mother came to me and made me enter the house (of the Prophet) and nothing surprised me but the coming of Allah's Apostle to me in the forenoon. Bukhari 7. 62. 90

Aisha was playing with dolls like any other 8 year old child would do. She was not ready for marriage and had no understanding of it.

Narrated 'Aisha:

I used to play with the dolls in the presence of the Prophet, and my girl friends also used to play with me. When Allah's Apostle used to enter (my dwelling place) they used to hide themselves, but the Prophet would call them to join and play with me. (The playing with the dolls and similar images is forbidden, but it was allowed for 'Aisha at that time, as she was a little girl, not yet reached the age of puberty.) (Fateh-al-Bari page 143, Vol.13)Bukhari 8. 73.151

Narrated Aisha:

The Prophet engaged me when I was a girl of six (years). We went to Medina and stayed at the home of Bani-al-Harith bin Khazraj. Then I got ill and my hair fell down. Later on my hair grew (again) and my mother, Um Ruman, came to me while I was playing in a swing with some of my girl friends. She called me, and I went to her, not knowing what she wanted to do to me. She caught me by the hand and made me stand at the door of the house. I was breathless then, and when my breathing became Allright, she took some water and rubbed my face and head with it. Then she took me into the house. There in the house I saw some Ansari women who said, "Best wishes and Allah's Blessing and a good luck." Then she entrusted me to them and they prepared me (for the marriage). Unexpectedly Allah's Apostle came to me in the forenoon and my mother handed me over to him, and at that time I was a girl of nine years of age. Bukhari 5.234

Having sexual feelings for small children is called pedophilia. According to Ayatollah Montazeri, the most revered Shiite cleric of Iran , the “marriage” of Muhammad and Aisha was a political maneuver to placate the enemies of Islam. He wrote: The reason for this marriage was that the Prophet was under the intense pressure by his enemies like Abu Lahab and Abu Jahl and was completely dependant of the protection of other tribes. Abu Bakr had a lot of tribal influence. And rejecting his offer, in those conditions, for the Prophet was not prudent. In reality this marriage was symbolic and not to satisfy his sexual instinct, because, as a rule a 53-year-old man cannot have sexual feelings for a 9-year-old girl.

This is nonsense. Abu Bakr was already a devout follower of Muhammad and his confidant. Abu Lahab and Abul Hakam (whom Muhammad derogatorily called Abu Jahl, father of ignorance) had nothing to do with Abu Bakr.  How can having sex with a child placate one's enemies?  Assuming this ridiculous excuse is true, what about Aisha?  Was she only a pawn for Muhammad’s political maneuvers? 

In one thing the Grand Ayatollah is right. As a rule a 53-year-old man cannot have sexual feelings for a 9-year-old girl, unless he is a pedophile.

The Islamocritic scholar, Abul Kasem, has demonstrated that in Islam there is actually no age limit for marrying a child. He found the following hadith which shows a Muslim man can marry an infant.  However should one of his adult wives suckle that infant both wives become haram to him.

Case of one of two wives suckling the other-If a man marry an infant and an adult and the latter should give milk to the former, both wives become prohibited with respect to that man [their husband], because if they were to continue united in marriage to him, it would imply the propriety of joint cohabitation with the foster-mother and her foster-daughter, which is prohibited, in the same manner as joint cohabitation with a natural mother and daughter-It is to be observed on this occasion, that if the husband should not have had carnal connexion with the adult wife, she is not entitled to any dower whatever, because the separation has proceeded from her, before consummation :-but the infant has a claim to her half dower. [Hedaya Vol. I Book III, page 71 (Ref. 6)]

Abul Kasem also quoted the story of Umar marrying a child just four or five years old.

Umme Kulthum was 4 or 5 years old when Umar married her.  This child was his most favourite wife (just like prophet Mohammad).  There is a great controversy about the identity of this child bride of Umar.  Many scholars claim that she was the daughter of Ali and Fatima.  Others say that Umme Kulthum was the posthumous daughter of Abu Bakar and Habiba.  Abu Bakar died (13 A.H.) a few months before Umme Kulthum was born.  She was the half sister of Aisha.  So, Umar asked Aisha for the hand of Umme Kulthum when she (Umme Kulthum) was only 4 - 5 years old.  Aisha agreed and Umar and Umme Kulthum got married.

According to Abul Kasem’s calculations, Umar was 56 years old when he married this little girl.   Why would he not wait for Umme Kulthum to reach the age of nine? Shouldn’t Umar follow the sunna (example) of his prophet?  The answer is that Muhammad did not set any limits for child marriage.   Ummar must have remembered when Muhammad expressed his desire to marry a crawling baby before death overtook him.  This story is reported by Ibn Ishac, the most authentic biographer of Muhammad.  Most other biographies are based on this monumental work of Ibn Ishak/Ibn Hisham

(Suhayli, ii.79: In the riwaya of Yunus I.I recorded that the apostle saw her (Ummu’l-Fadl) when she was baby crawling before him and said, ‘If she grows up and I am still alive I will marry her.’ But he died before she grew up and Sufyan b. al-Aswad b. Abdu’l-Asad al-Makhzumi married her and she bore him Rizq and Lubaba….(Ref.3, page 311)