This happened; I couldn't verify any inaccuracies from the books.
Tenth level Cleric was hasted and in melee.
He took a 5-foot step backwards, and cast a spell.
He then took a 5-foot step forward and performed his single hasted attack with his mace.
No attacks of opportunity were incurred from the person he was in melee with.
This just seems wrong, but I can't find anywhere that states you can't have two 5-foot steps if you’re hasted or that moving twice will incur an attack of opportunity.
I did find the exact example of backing up and casting in the back of the new PH, and found that you can cast with just one hand.
Was he right?
Thanks for any assistance either way.

Tenth level Cleric was hasted and in melee.
He took a 5-foot step backwards, and cast a spell.
He then took a 5-foot step forward and performed his single hasted attack with his mace.
No attacks of opportunity were incurred from the person he was in melee with.
This just seems wrong, but I can't find anywhere that states you can't have two 5-foot steps if you’re hasted or that moving twice will incur an attack of opportunity.
I did find the exact example of backing up and casting in the back of the new PH, and found that you can cast with just one hand.
Was he right?
Thanks for any assistance either way.
