Question on SQL Developer: how to get ride of quotes for .txt file when exporting query result?

Hi everyone,

One of the my user has to use Oracle SQL Developerr instead of TOAD. 

In TOAD when you export the query result to .txt file, it gives you something like this:

23       78861          USD           AUG-10            E

However, in SQL Navigator, it give you something like this:

23       78861         "USD"        "AUG-10"         "E" 

Question: how to get ride of the quotes there?

Thanks,

Ning