Samsaran - Mystic Past Life Question

[Laukai]

I have a question that could possibly break this race, as I have no idea how to handle it... What do you do when you have an arcane caster (Wizard/Sorcerer/etc...) who is a Samsaran, and was a Summoner in a past life...

Summon Eidolon:
What happens when a player wants to add the Summon Eidolon spell from the Summoner's spell list? How do you determine what shows up?

[Lelomenia]

You don’t have an eidolon, so probably RAW is nothing happens. Could call one of these though. (You wouldn’t have any control over it)

[blahpers]

The same thing that happens when a rogue successfully uses Use Magic Device to activate a scroll of summon eidolon--nothing, because the rogue doesn't have an eidolon.