Android plugin SOAP client side

I am porting an IOS game to Android.
Players can login using SOAP webservice.
I have used ksoap2 and can access the webservice from Android with Java.
I have a “connect” button in Unity that should call the webservice.
and some info (string name & password) should be sent to Java and (boolean or int , string) should be return from Java to C# method for login.
I am using an AsyncTask() for executing the call to the webservice.
I can call a Java method from C# using AndroidJavaClass and AndroidJavaObject. (to pass a string or int)
But can not execute my AsyncTask().
So first
Is it correct to use AsyncTask() to call the webservice from unity ?
and second
How to do it ?

Any help, critics, links will be very Welcome !

ok i could call the web service without using the async task but runOnUiThread() and enable Strict mode from java