The mistakes’ author points out a grammatical error in The Family of Imran (3:59). The verse under consideration is the one which talks about birth of Jesus:

إِنَّ مَثَلَ عِيسَى عِنْدَ اللهِ كَمَثَلِ آدَمَ خَلَقَهُ مِنْ تُرَابٍ ثُمَّ قَالَ لَهُ كُنْ فَيَكُونُ

He writes:

3/59: Kun feekunu should be Kun fekaana. [1]

i.e. it should be كن فكان instead of كن فيكون

This in an amazing ‘mistake’ pinpointed by him! Most likely, he has been mislead by translations. The translators of Quran usually translate it in such a way that فكان seems plausible. The translation of كن فيكون would be: “God said to him: ‘Be’ and he started coming into being” i.e. in the sense of past continuous.

So, the meaning of كن فيكون actually is that when God orders something that how and through what stages it should come into being, it starts coming into being through these stages. That’s what Quran is telling about Jesus (peace be upon him) here i.e. He said to him: “come into being” then his ‘coming into being’ completed in 9 months i.e. the same duration in which a child develops in the womb of his mother. To know more details see Mary 19: 18-24

[1] http://www.1000mistakes.com/1000mistakes/index.php?Page=002_002_001_001 (Retrieved on July 11, 2013)