[RPG] How does Empower Spell interact with criticals

critical-hitdnd-3.5emetamagic

How is the the total damage of a spell calculated, if it is enhanced by the Empower Spell metamagic feat and a critical hit is rolled?

According to the d20 SRD Empower Spell feat entry:

Benefit: All variable, numeric effects of an empowered spell are increased by one-half.

Still according to the SRD in the note about Multiplying:

Sometimes a rule makes you multiply a number or a die roll. As long as you’re applying a single multiplier, multiply the number normally. When two or more multipliers apply to any abstract value (such as a modifier or a die roll), however, combine them into a single multiple, with each extra multiple adding 1 less than its value to the first multiple. Thus, a double (×2) and a double (×2) applied to the same number results in a triple (×3, because 2 + 1 = 3).

So, if for example, a 5th level wizard casts an Empowered Shocking Grasp (5d6 damage) and scores a critical hit, will she:

• roll 10d6, the add 50% of the total (i.e. the Multiplying rule does not apply), or
• roll 5d6 plus 50% plus another 5d6 (i.e. by the Multiplying rule: 5d6×2×1.5 = 5d6×(2+0.5))?