Shapeshifting and spellbook

Hi again.
Now i got another problem :P Ive made an spellbook with some spells but the problem is that if the hero shapeshift's, the spell book icon is still there but there are no spell in it longer . Is there anyway to solve it?

Once you add the shapeshifting ability, you must make it permanent if you want it to remain in the spellbook.

native UnitMakeAbilityPermanent (unit whichUnit, boolean permanent, integer abilityId) returns boolean

The shapeshift ability is not in the spellbook. The spellbook is an normal abillity that hero have from begining, while shapeshift is an hero ability that hero can learn at lvl 6

Well... Make the other abilities in the spellbook permanent.