The only entrelac scarf pattern I could find was from knitty, but I don't think it's the one you're looking for. The vogue knitting website only goes back to 2005 in patterns it seems and it's not easy to find what you're looking for. Even typing "entrelac" in their search section comes up with nothing.
Because I'm enamored with entrelac myself, I figured I'd do a little searching for patterns involving it. I found a beautiful shawl, but I seriously doubt it's what you're looking for : http://charlotteyarn.blogspot.com/2007/09/jojoland-entrelac-shawl.html.
Anyway, sorry I wasn't more help, and maybe someone else will actually have the pattern. Meanwhile I'm going back to my search because this stuff is gorgeous!