How can I print envelopes on Bizhub C650? Tried, but won't work....

[keystonenew]

I've heard you can print enelopes on the C650, but think a 5.75" w x 4.375" h,
is too small to feed thru the machine? Can I feed w/ the flap on the side? That
way, it fits in the size parameters. Thanks for any advice.