I am unable to type a backslash (\) into any text fields. I've also seen this happen with other Java apps.

Early versions of Swing had this challenge. Update your swingall.jar to Swing 1.1 or 1.2 and use JVM 1.1.6 or later. Also, this appears to continue to be a challenge on non-English keyboards. Sun promises a solution to this in the near future.
Work around
Applies to
file list, pure java standalone jar, including and excluding files, selecting directories

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