CRM 2011: Xrm.Page.data.entity.attributes.get returning null whilst record has a value

Hi, 

I have added a new field 'iscollege' to Dynamics CRM 2011 Entity. On form load I am checking the value of 'iscollage' as following:  

function form_onLoad(context) {     alert(Xrm.Page.data.entity.attributes.get("iscollage"));
}

Its returning null, whilst record has a value, in advance search the value of 'iscollage' is 'Yes' 

Can anyone please help me to figure out the reason.

Thanks