[quote=Shurik]When my Human Wizard wears HeavyArmor he can use only scroll
And he also can't gain HeavyArmor Proficiency feat wich is required Medium ArmourProficiency wich I cant get too ).
Don't know about other races[/quote]

Maybe it is because you didn't have proficiency in it?
Maybe heavy armor doesn't allow spellcasting? I know I tried it with a Githyanki in medium armor (I stole Lae-Zel's amor) and I was able to cast spells using her armor and longsword.

As for getting to heavy proficiency, you just need to start as a race that has at least medium armor prof, then at level 4 you can select heavy, right?