No, Big D. In the Japanese Version, Ultimecia clearly creates him on the spot, saying that she will take the party's most powerful feelings and force them to face them. It's something along the lines of "From your feelings, I shall make the most powerful of things." That translation's not exact, so bear with me.

She then says something along the lines of "The greater they are, the greater shall be your suffering! Fufu!"

The German Version is also similar in this respect:

"What is the absolute power for you? ["For you" meaning "in your opinion"]
The stronger your will, the bigger your pain.
Face the power!"

There is a greaaaat degree of variance between the English, German, and Japanese lines, with the German lines being most similar to those in Japanese.

I don't have access to all of the Japanese lines for the game, but I do have a complete German translation for the entire battle sequence with Ultimecia and Griever. Compare it to the English Version:

-English-

::Ultimecia gets pounded on for a while::

"The most powerful GF..."
"...You shall..."
"...SUFFER...!"
"HAHAHA..."

:riever comes and it gets pounded on for a while::

"The GF's true power...
Allow me...
To show you...!
Griever! Make them bleed!"

::Ultimecia prepares to Junction with Griever::

"I shall junction myself unto Griever!"

::The Junctioned Ultimecia with Griever is defeated::

"Rghaah..."

::Ultimecia rises up with her full power from having absorbed the power of the other Witches, absorbing the universe even as we speak; she then fights SeeD::

"I am Ultimecia.
Time shall compress...
...All existence denied.
Reflect on your...
Childhood...
Your sensation...
Your words...
Your emotions...
Time...
It will not wait...
No matter...
...how hard you hold on.
It escapes you.
And..."


(Translated courtesy of Eckesachs)
-German Version-

::Ultimecia gets pounded on for a while::

"What is the absolute power for you?
The stronger your will, the bigger your pain.
Face the power!"

:riever comes and it gets pounded on for a while::

"Memory loss?
...that is what you fear?
Show them your true power!
Show them, Griever!"

::Ultimecia prepares to Junction with Griever::

"The game is over!
I will junction Griever!"

::The Junctioned Ultimecia with Griever is defeated::

"Ughhh..."

::Ultimecia rises up with her full power from having absorbed the power of the other Witches, absorbing the universe even as we speak; she then fights SeeD::

"I am Ultimecia.
I merge time.
I deny existence.
Memories...
from far childhood.
Those sensations...
Those words...
Those feelings...
By growing up,
much is lost.
Time does not wait.
You keep hold of it,
and yet it melts away.
But now..."


Edit: Damn, we're all leaping to the attack. You guys got Posts in before me.