A quick search of the Strathclyde University site gave the following URL for Eucalb:
This is slightly different to the one you cite so this may be the problem.
However, I could not connect either so the server may be down currently too!
C. Graham Clark, Ph.D.
Department of Infectious and Tropical Diseases,
London School of Hygiene and Tropical Medicine,
Keppel St., London WC1E 7HT
Entamoeba Homepage: www.lshtm.ac.uk/mp/bcu/enta/home.htm