adding helper applications to browser?

[Robert Huff]

	(This may not be the best place to ask this; if not, I hope
someone will point me to a better forum.)

	In Firefox 13 and SeaMonkey 2.9, there appears to be no
internal way to add a new mime-type+helper application.
	1) Is this correct?  Am I missing something, or do is something
mis-configured?
	2) If it is: is there a (preferred) add-on that will do this?
	3) If there's no add-on ... is there any way other than
hand-editing mimeTypes.rdf?

	Respectfully,


					Robert Huff