SAML 2.0 Single Log Out (SLO) issue with iOS & PhoneGap

I am using Phonegap and jQuery AJAX calls to perform logout like below

$.ajax({ url: logoutURL, type:"POST", data:{}, cache:false,

success:function(data, textStatus, jqXHR){........},

error:function(jqXHR, textStatus, errorThrown){  

     alert("Logout Failed.");  

     $.mobile.hidePageLoadingMsg();

     enableAllButtons();}});          

the logout URL is a SAML 2.0 Single Log Out (SLO) URL. I have tested this on Android it is working perfectly fine. But when I tried the SLO on ios specifically iPad ios 6.1.3 it will fail and it returns me with a http 0.

I just found out from the IDP log that for android it has a warning of "Client Certificate error, IP address" but it will then automatically attempt to create outgoing SSL connection without trusted certificates. on the other hand, on iOS it does not continue the connection after the signed assertion was issued.

How can I get this solved or is there a way for me to bypass the cert problem?

All advice are appreciated.