Effendy,
I'm not sure what the particular error that you are getting is. However, if you checkout openacs with the -r oacs-4-6 switch (the tip of the branch) and dotlrn with the -r dotlrn-1-0 switch you should have a much better chance of a successful install. Alternatively you could wait for the new releases of openacs and dotlrn that should be just around the corner.