I'm not certain how you would be distributing the document... you might say:

"Attached is the new version of "X" please replace any prior versions and distribute to your staff."

or

"Attached is the new "X" form. Please distribute this to your staff."

Make certain if this is a new version, you put the month/year on the bottom as a footer so people know that they are using the correct form like:

LS-561 (06/09)
(Rev. 12/0