I believe you could use a relative URL tag and not an absolute tag.
Just like HTML.
Dont Do this:
getUrl("file://E:/pdfs/page1.pdf")
(because you don't know if other people will already have a E drive designated for the CD-ROM [obviously, you already know])
Do this:
getUrl("file://pdfs/page1.pdf")
Remove the E: and be sure everything works in Dreamweaver using Link Checker or make sure everything is in the same native folder.
It's a bit difficult to explain, but there are 2 ways to specify a file location: Absolute and Relative.
They act the way they sound, an Absolute File Location specifys the exact location (E:/pdfs/page1.pdf) <--- This file is located only on the E drive in the folder pdfs.
A relative file location assumes the file your looking for exists within the same folder. (pdfs/page1.pdf) <--- Without the E:// the computer (Mac/PC) assumes that the pdfs folder is nearby (within the same directory) and it doesn't matter what letter the drive is.
Hope this helps.