blackberry - Crical Call Io Exception:Critical tunnel Failure problem in black berry -

in app connecting web,it not showing error when installed app in phone shows critical call io exception:critical tunnel failure. why error occurs.please me.

thank

follow link can solve problem:http://www.blackberry.com/knowledgecenterpublic/livelink.exe/fetch/2000/348583/800451/800563/what_is_-_different_ways_to_make_an_http_or_socket_connection.html?nodeid=826935&vernum=0

and can use following sample code:

private static string getconnectionstring(){ string connectionstring=""; if(wlaninfo.getwlanstate()==wlaninfo.wlan_state_connected){ connectionstring=";interface=wifi"; }

 else if((coverageinfo.getcoveragestatus() & coverageinfo.coverage_mds) == coverageinfo.coverage_mds){      connectionstring = ";deviceside=false"; }     else if((coverageinfo.getcoveragestatus() & coverageinfo.coverage_direct)==coverageinfo.coverage_direct){         string carrieruid=getcarrierbibsuid();         if(carrieruid == null) {             connectionstring = ";deviceside=true";         }         else{              connectionstring = ";deviceside=false;connectionuid="+carrieruid + ";connectiontype=mds-public";             }                        }  else if(coverageinfo.getcoveragestatus() == coverageinfo.coverage_none)     {      } return connectionstring; }