??? Reference to non-existent field 'net_read_only' error creating SOM network by using either newsom or selforgmap functions

Hello,

I'm trying to generate a Self Organizing Map for clustering information. However when trying to create the net either using newsom function, selforgmap function or Neural network classification tool (nctool) I get the following error even when using Matlab Demo codes:

net=selforgmap([8 8])
??? Reference to non-existent field 'net_read_only'.

Error in ==> network.subsasgn>network_subsasgn at 42
  if ~isempty(strmatch(field,FIELD_NAMES.net_read_only,'exact'))

Error in ==> network.subsasgn at 11
net = network_subsasgn(net,subscripts,v,netname);

Error in ==> network.network>setnet at 174
net = subsasgn(net,subscripts,value);

Error in ==> network.network>new_network at 164
net = setnet(net,'numInputs',numInputs);

Error in ==> network.network at 72
  net = new_network(varargin{:});

Error in ==> selforgmap>create_network at 108
  net = network(1,1,0,1,0,1);

Error in ==> selforgmap at 72
    net = create_network(param);

Any suggestion for why is happening that would be really appreciated, since I'm blocked at that point and I can not continue my task. Could it be a SO/non-Matlab problem? I'm currently running Matlab 7.11.0 in Vista.

Thanks a lot!