ATTN JMS: Another Original casting question

In a late interview(*) Tamlyn Tomita expressed:
"If my memory serves me correctly, I think I auditioned
for the part and got it rather quickly, because the show
needed to replace the actor they had originally cast, and
they were ready to shoot."

I never before heard about a first cast for Takashima.
Now, is Tamlyn remembering correctly, and if so who's
the actor replaced (and why)?

Regards
Stefan

(*) The B5 Q&A follows Eureka and Stargate:
http://eguide-online.de/eureka/index.php?seite=artikel&aktion=show&id2=424#english

--
Garibaldi: "I'm not authorized for that kind of information."
[Matters of Honor]


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