64bit Vista

I'm running a 64bit version of Vista. I've been running the 32bit binaries and they seem fine but I've noticed a small issue when I call Yap using the -L flag. Basically I get a number of pipe ('|') characters output. For example, if I have a file as follows: file.pl: :- initialization(main). m(a). main:-setof(A,m(A),List),write(List),nl. and i run: yap -L file.pl the output i get is: | | | | [a] Is this an issue with my OS (I don't get this under Linux)? Are there any Yap binaries available for 64bit windows? The actual prolog results seem fine and the pipes appear on cerr rather than cout I think. Many thanks jc