hyperlinks to pdf files

[Plunket, Paddy]

Hello people
We have a number of electronic journal subscriptions which provide the full
text of articles as pdf files which we have placed on our intranet.
Unfortunately the links to these behave erratically.  Hyperlinks are
generated in frontpage98, and sometimes they work for some of the articles
and sometimes they don't.  On the same machine during the same session some
links will open their associated article, while others will just launch the
acrobat reader in the browser with a blank page.  If you right click and
choose "save target as" the article will download as a file even if it wont
open.  Then on the same machine during a different session, nothing will
open, you just get the acrobat reader and the blank page, even for articles
that opened five minutes ago!  Does anyone know why, or what we might do to
fix this.  I would be grateful for any suggestions as we are stumped as to
what is causing this.
We are using IIS4 and Explorer 3.02. 

Paddy Plunket
Sources, Specialist Education Services
PO Box 12-188, Wellington
PH 04 460 0826 Fax 04 460 0842