function sendForm(){
 
 		var formOK = 1;

        if (document.f1.Naam.value =="")
		 {alert("Enter your name.");
		 (document.f1.Naam.focus());
		 formOK = 0;
		 }
		 
		 else
		if (document.f1.Companie.value =="")
		 {alert("Enter the name of your companie.");
		 (document.f1.Companie.focus());
		 formOK = 0;
		 }
		
		/*-- email check --*/		 
		else
		if ((document.f1.email_van.value =="") && (formOK==1))
		 {alert("Enter your e-mail address.");
		  (document.f1.email_van.focus());
		  formOK = 0;
		 }
		 
		else
		if ((document.f1.email_van.value.indexOf("@") ==-1) && (formOK==1))
		  {alert("Enter a valid e-mail address.");
		 (document.f1.email_van.focus());
		 formOK = 0;
		 }
		 
		else
		if ((document.f1.email_van.value.indexOf(".") ==-1) && (formOK==1))
		  {alert("Enter a valid e-mail address.");
		 (document.f1.email_van.focus());
		 formOK = 0;
		 }

		/*-- end email check --*/

		 if (formOK==1) {
		  document.f1.submit();
		 } 
}