Cannot upload some files using nitrogen element_upload

try the nitrogen upload function in nitrogen project homepage
( http://nitrogenproject.com/web/samples/upload ) and also setup a nitrogen in my own computer to test the function.
Some files can be uploaded well but some files cannot be uploaded, for
example this file:
http://groups.google.com/group/nitrogenweb/web/webmc.zip
I look at the console and it prints these lines:
ERROR erlang code crashed:
File: appmod:0 Reason: {badarg,[{erlang,list_to_integer,[[133,221],16]},

             {yaws_api,do_parse_spec,5},
             {wf_handle,handle_request,2}, 
             {yaws_server,deliver_dyn_part,8}, 
             {yaws_server,aloop,3}, 
             {yaws_server,acceptor0,2}, 
             {proc_lib,init_p_do_apply,3}]}

Req: {http_request,'POST',{abs_path,"/en/samples/upload"},{1,1}}
Stack: [{erlang,list_to_integer,[[133,221],16]},

    {yaws_api,do_parse_spec,5},
    {wf_handle,handle_request,2}, 
    {yaws_server,deliver_dyn_part,8}, 
    {yaws_server,aloop,3}, 
    {yaws_server,acceptor0,2}, 
    {proc_lib,init_p_do_apply,3}]