[Bluej-discuss] Problem using submitter -- MIME issues

[Stephen Edwards]

Brad Richards wrote:
> Unfortunately, after updating Java and BlueJ for the 
> new semester, the submission process no longer works.
[...]
> Java version 1.6.0_02
[...]
> 	javax.activation.UnsupportedDataTypeException: no object DCH 
> for MIME type multipart/mixed;

This is just some rambling for the BlueJ developers to try to help
track this one down.  I'm guessing that the javax.mail package is
being used to send mail.  With JDK v1.6, Sun started bundling the
javax.activation framework into the JDK run time--but *not* the
javax.mail framework.  The javax.mail classes need to be in a
classloader that is visible to the activation framework classes in
order to work, or you'll see this error.

Since extensions (like the submitter) run under their
own separate class loader, this could potentially cause
the problem described here (if the javax.mail classes are bundled
in the submitter extension, for example).

I could be off, but I'd expect this error to show up with JDK 1.6,
but still work fine with JDK 1.5.

-- Steve

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