xij
looks to be matrix in the BUGS model, but you have at as a vector in the data. This should work:
list(n=2, k=5, yij=structure(.Data=c(1, 1, 1, 1, 1, 0, 0, 0, 0, 0), .Dim=c(2,5)),
xij = structure(.Data=c(0.0494063719, -0.078101264, 0.2748560749, 0.1245743393, -2.531242809, .6849338859, 0.5302062384, 0.7828560148, -0.012341452, 0.5128471157), .Dim=c(2,5)),
ui = c(0.5031197054, 0.5031197054, 0.5031197054, 0.5031197054, 0.5031197054, -2.13785637, -2.13785637, 2.13785637, -2.13785637, -2.13785637))