Problem with filepath in script

I'm trying to pass a filepath in a button script (MAS 200 "Execute on Server"). I can't get the variable to take the literal string that I assign. Here's what I mean:

sample script:

sAttach = "\\fileserver\folder\file.pdf"

retVal = oSession.AsObject(oSession.UI).MessageBox("",sAttach)

The result is not "\\fileserver\folder\file.pdf", but 

fileserver

folder

file.pdf

Everywhere there were backslashes in the string, a new line gets inserted and the backslash doesn't appear. This behavior doesn't happen with non-Sage vbs scripts. Has anybody ever run into this?