$(document).ready(function(){

			// form submit
			$("A#form_submit_btn").click(function () { 
				
				missing_f = "";
				
				// check fields
				if( document.forms['form1'].ime.value == "" ){ missing_f += "\n - Ime i prezime"; }
				// if( document.forms['form1'].interes.value == "" ){ missing_f += "\n - Interes"; }
				if( document.forms['form1'].tvrtka.value == "" ){ missing_f += "\n - Tvrtka"; }
				if( document.forms['form1'].poruka.value == "" ){ missing_f += "\n - Poruka"; }
				if( document.forms['form1'].email.value == "" ){ missing_f += "\n - Email"; }
				if( document.forms['form1'].tel.value == "" ){ missing_f += "\n - Telefon"; }
				
				if( missing_f != "" ){
					
					alert("Molimo popunite sljedeća polja:" + missing_f);
					
				}
				else {
					$("#form1").submit(); 	
				}
							
				
				return false;
				 
			});	

			
		});