Welcome to the CHICKEN Scheme pasting service

function removeWeirdChars(t)
{
	var text=t.value;
	var result="";
	var allowed="the quick brown fox jumps over the lazy dog.THE QUICK BROWN FOX JUMPS OVER THE LAZY DOG._-%?1234567890/:";			

	for (var i=0;i<text.length;i++)
		if (allowed.indexOf(text.charAt(i))>=0)
			result=result+text.charAt(i);
	if (result!=text)
		t.value=result;
}