I am writing my own save method for the user custom page which is created by using the standard controller as a User.

when i am trying to write the controller code that time it is not allowing the use.UserType = cntr.UserType .Giving compilatin Error like 

Remaing fields are allowed to write.

Why it is not allowing to compile the controller?

Can anyone phased this situation?

 how can i use for UserType Field.

For more clarity on my problem i am just giving my custom page code and controller code  which is given below.

custom user Page :

<apex:page standardController="User" extensions="usercontroller" >

<apex:form >
<apex:pageBlock >
<apex:pageBlockSection title="User Information">

<apex:inputField id="userFirstName" value="{!user.firstname}"/>
<apex:inputField id="userLastName" value="{!User.lastName}"/>
<apex:inputField id="userAlias" value="{!User.alias}"/>
<apex:inputField id="userEmail" value="{!User.email}"/>
<apex:inputField id="userUserName" value="{!User.UserName}"/>
<apex:inputField id="userLicense" value="{!User.UserType}"/>
<apex:inputField id="userEmailEncoding" value="{!user.title}"/>
<apex:inputField id="userCommunityNickName" value="{!User.communityNickName}"/>
<apex:inputField id="userrole" value="{!User.UserRoleId}"/>
<apex:inputField id="userProfileId" value="{!User.ProfileId}"/>
<apex:inputField id="userEmailEncodingKey" value="{!User.EmailEncodingKey}"/>
<apex:inputField id="userlanguage" value="{!User.LanguageLocaleKey}"/>
<apex:inputField id="userlocale" value="{!User.LocaleSidKey}"/>
<apex:inputField id="userTimezone" value="{!User.TimeZoneSidKey}"/>
</apex:pageBlockSection>

<apex:pageBlockButtons >
<apex:commandButton action="{!Save}" value="Save"/>
<apex:commandButton action="{!cancel}" value="cancel"/>
</apex:pageBlockButtons>

</apex:pageBlock>
</apex:form>
</apex:page>

Custom controller:

public class usercontroller {

private User cntr;
private final ApexPages.StandardController controller;

    public usercontroller(ApexPages.StandardSetController controller) {
   
   

    }

 //
    public usercontroller(ApexPages.StandardController controller) {

         this.controller = controller;

    cntr= (User )controller.getRecord();

    }

   
public PageReference Test()
  
     {
            
        PageReference pageRef = new  PageReference('https://na6.salesforce.com/apex/newuser');
       
         pageRef.setRedirect(true);
         return pageRef ;
      
      
    }  

public PageReference Save()
  
     {
    
     User use = new User();
    
     use.firstname = cntr.firstname;
     use.lastName =cntr.lastName;
     use.alias =cntr.alias;
     use.email =cntr.email;
     use.UserName =cntr.UserName;
     use.UserType =cntr.UserType;
     use.title =cntr.title;
     use.communityNickName =cntr.communityNickName;
     use.UserRoleId =cntr.UserRoleId;
     use.ProfileId =cntr.ProfileId;
     use.EmailEncodingKey =cntr.EmailEncodingKey;
     use.LanguageLocaleKey =cntr.LanguageLocaleKey;
     use.LocaleSidKey =cntr.LocaleSidKey;
     use.TimeZoneSidKey =cntr.TimeZoneSidKey;
    
    
    
    
    
      insert use ;

            
        PageReference pageRef = new  PageReference('https://c.na6.visual.force.com/apex/users');
          pageRef.setRedirect(true);
         return pageRef ;
      
      
    } 

}