the problem is that NuSOAP's soap client class has the same name as the now built-in soap client class that comes with php5, hence the redeclaration error.
there are 5 files in the NuSOAP lib that need to have all occurences of 'soapclient' replaced with something else. I used 'soapclientnu'
doing this find/replace on all the nusoap files fixed it up for me.