nxdomain error

[NavaTux]

what is error nxdomain,when i open the sample application this error
shown like these


ERROR REPORT==== 27-Mar-2010::17:49:30 ===
Error : nxdomain

=ERROR REPORT==== 27-Mar-2010::17:49:30 ===
Error : nxdomain

=ERROR REPORT==== 27-Mar-2010::17:49:30 ===
Error : nxdomain

=ERROR REPORT==== 27-Mar-2010::17:49:57 ===
** Generic server <0.104.0> terminating
** Last message in was {tcp,#Port<0.2494>,
                            <<"POST /web/stream/hello HTTP/1.1\r
\nHost: localhost:8000\r\nUser-Agent: Mozilla/5.0 (X11; U; Linux i686;
en-US; rv:1.9.0.8) Gecko/2009033100 Ubuntu/9.04 (jaunty) Firefox/
3.0.18\r\nAccept: text/plain, */*\r\nAccept-Language: en-us,en;q=0.5\r
\nAccept-Encoding: gzip,deflate\r\nAccept-Charset:
ISO-8859-1,utf-8;q=0.7,*;q=0.7\r\nKeep-Alive: 300\r\nConnection: keep-
alive\r\nContent-Type: application/x-www-form-urlencoded;
charset=UTF-8\r\nX-Requested-With: XMLHttpRequest\r\nReferer:
http://localhost:8000/web/stream/hello\r\nContent-Length: 281\r
\nCookie:
SESS23e7e949e8d5d6643636d5138b3fcde3=3b8cdce3644d0a356dfa3cf44303503f;
wf=T6Wps4NQAAAAXHicy2DKY2XYVqx0lC-
DKT2FQaKkPLOkJLUovrikKDUx1yEnPzkxJyO_uISBgSEeiBmYixiY8ShjBqpYxgAFADUcGlY
\r\nPragma: no-cache\r\nCache-Control: no-cache\r\n\r
\npostbackInfo=irS25INQAAAATHicy2DKY2XYVqx0lC-
DLZuBpSAxPTWFgbM0LyU1LTMvNSWFgTU5Pze1BFUMmc1VnpoUX1xSlJqYCwCMUBjr&domState=OjByKYNQAAAAdXicFY0xDgIxDAStAxqEaGioeQk_sayzITk55BQv5Gf8gH9xKVejmU3T60DfuP3OTkS7NCkdP-
JZBbXFMvYFVlYXGHcJnsXdVGmP9raBT_3Bcy0GXrM-
la7oGbDGgWZS7l43JdXA1hcaJ8sfh7AlOw">>}
** When Server state == {state,
                            {mod,
                                {init_data,{52013,"127.0.0.1"},"nava-
laptop"},
                                [],ip_comm,#Port<0.2494>,
                                httpd_conf__0_0_0_0__8000,undefined,
[],
                                undefined,undefined,undefined,
[],undefined,
                                undefined},
                            <0.90.0>,accept,
                            {httpd_request,parse,[{nolimit,10240}]},
                            infinity,false,
150000,#Ref<0.0.0.1011>,undefined,
                            undefined}
** Reason for termination ==
** {{badmatch,socket_closed},
    [{httpd_response,send_body,3},
     {httpd_response,generate_and_send_response,1},
     {httpd_request_handler,handle_response,1},
     {gen_server,handle_msg,5},
     {proc_lib,init_p_do_apply,3}]}

=ERROR REPORT==== 27-Mar-2010::17:49:59 ===
** Generic server <0.94.0> terminating
** Last message in was {tcp,#Port<0.1782>,
                            <<"POST /web/stream/hello HTTP/1.1\r
\nHost: localhost:8000\r\nUser-Agent: Mozilla/5.0 (X11; U; Linux i686;
en-US; rv:1.9.0.8) Gecko/2009033100 Ubuntu/9.04 (jaunty) Firefox/
3.0.18\r\nAccept: text/plain, */*\r\nAccept-Language: en-us,en;q=0.5\r
\nAccept-Encoding: gzip,deflate\r\nAccept-Charset:
ISO-8859-1,utf-8;q=0.7,*;q=0.7\r\nKeep-Alive: 300\r\nConnection: keep-
alive\r\nContent-Type: application/x-www-form-urlencoded;
charset=UTF-8\r\nX-Requested-With: XMLHttpRequest\r\nReferer:
http://localhost:8000/web/stream/hello\r\nContent-Length: 281\r
\nCookie:
SESS23e7e949e8d5d6643636d5138b3fcde3=3b8cdce3644d0a356dfa3cf44303503f;
wf=o8GduYNQAAAAXHicy2DKY2XYUax0lC-
DKT2FQaKkPLOkJLUovrikKDUx1yEnPzkxJyO_uISBgSEeiBmYixiY8ShjBqpYxgAFADXKGlg
\r\nPragma: no-cache\r\nCache-Control: no-cache\r\n\r
\npostbackInfo=dhFlWINQAAAATHicy2DKY2XYXqx0lC-
DLZuBpSAxPTWFgbM0LyU1LTMvNSWFgTU5Pze1BFUMmc1VnpoUX1xSlJqYCwCMlxjs&domState=QAousINQAAAAdXicFY0xDgIxDAStAxqEaGioeQk_sayzITk55BQv5Gm8gH9xKVejmU3T60DfuP3OTkS7NCkdP-
JZBbXFMvYFVlYXGHcJnsXdVGmP9raBT_3Bcy0GXrM-
la7oGbDGgWZS7l43JdXA1s80TpY_iFglRA">>}
** When Server state == {state,
                            {mod,
                                {init_data,{52009,"127.0.0.1"},"nava-
laptop"},
                                [],ip_comm,#Port<0.1782>,
                                httpd_conf__0_0_0_0__8000,undefined,
[],
                                undefined,undefined,undefined,
[],undefined,
                                undefined},
                            <0.90.0>,accept,
                            {httpd_request,parse,[{nolimit,10240}]},
                            infinity,false,
150000,#Ref<0.0.0.1096>,undefined,
                            undefined}
** Reason for termination ==
** {{badmatch,socket_closed},
    [{httpd_response,send_body,3},
     {httpd_response,generate_and_send_response,1},
     {httpd_request_handler,handle_response,1},
     {gen_server,handle_msg,5},
     {proc_lib,init_p_do_apply,3}]}