function isEmailAddr(email)
			{
				var pattern=/(^[\-_\.a-zA-Z0-9]+)@((([0-9]{1,3}\.){3}([0-9]{1,3})((:[0-9])*))|(([a-zA-Z0-9\-]+)(\.[a-zA-Z]{2,})+(\.[a-zA-Z]{2})?((:[0-9])*)))/;

				if (email == ""){
					return false;
				}
				else if (email.search(pattern) == -1) {
					return false;
				}

				return true;
			}

			function validateRegistrationForm()
			{
			    var valid = true;

				if ( document.getElementById("voornaam") != null )
				{
					if ( document.getElementById("voornaam").value == "" )
					{
						document.getElementById("voornaam_error").style.display = "inline";
						valid = false;
					}
					else
						document.getElementById("voornaam_error").style.display = "none";
				}

				if ( document.getElementById("achternaam") != null )
				{
					if ( document.getElementById("achternaam").value == "" )
					{
						document.getElementById("achternaam_error").style.display = "inline";
						valid = false;
					}
					else
						document.getElementById("achternaam_error").style.display = "none";
				}
				
				if ( document.getElementById("email_error") != null )
				{
					if ( !isEmailAddr(document.getElementById("email").value) )
	               	{
	               		document.getElementById("email_error").style.display = "inline";
	               		valid = false;
	               	}
	               	else
	               		document.getElementById("email_error").style.display = "none";
                }

				if ( document.getElementById("code").value == "" )
               	{
               		document.getElementById("code_error").innerHTML = strErrorEnterCode;
               		document.getElementById("code_error").style.display = "inline";
               		valid = false;
               	}
               	else
				{
					if ( document.getElementById("code_error") != null )
						document.getElementById("code_error").style.display = "none";
				}

				if ( document.getElementById("age") != null )
				{
					if ( isNaN( document.getElementById("age").value ) || document.getElementById("age").value == "" )
					{
	               		document.getElementById("age_error").style.display = "inline";
	               		valid = false;
					}
					else
						document.getElementById("age_error").style.display = "none";
				}
				
				if ( document.getElementById("number") != null )
				{
					if ( document.getElementById("number").value == "" )
					{
	               		document.getElementById("number_error").style.display = "inline";
	               		valid = false;
					}
					else
						document.getElementById("number_error").style.display = "none";
				}
				
				if ( document.getElementById("company") != null )
				{
					if ( document.getElementById("company").value == "" )
					{
	               		document.getElementById("company_error").style.display = "inline";
	               		valid = false;
					}
					else
						document.getElementById("company_error").style.display = "none";
				}
				
				if ( document.getElementById("eula") != null )
				{
					if ( document.getElementById("eula").checked != true )
					{	               		
						valid = false;
						alert( strErrorAcceptEula );
					}
				}

				
				
				if ( document.getElementById("usage1") != null )
				{
					if ( document.getElementById("usage1").checked == false && document.getElementById("usage2").checked == false )
					{
						valid = false;
						try
						{
							document.getElementById("usage_text").style.display = "table-cell";	
						}
						catch(ex)
						{
							document.getElementById("usage_text").style.display = "inline";	
						}						
					}
					else
					{
						document.getElementById("usage_text").style.display = "none";			
					}
				}
								
				return valid;
			}