function checkForm(form){

 ffields = new Array('name','email','subject','message');

 for(z=0;z<ffields.length;z++) {
  
  curField = form.elements[ffields[z]];
  curField.style.backgroundColor = 'white';
  if (curField.value == "" || (whspace_check(curField.value)==false) || (spam_check(curField.value)==false) || (curField.value == 'fill in '+ffields[z])) {
   curField.style.backgroundColor = '#ffb5b6';
   curField.value = 'fill in '+ffields[z];
   curField.focus();
   return false;
  }
 }

  form.submit_mail.value = 'submitting...';
  return true;
}


function whspace_check(fieldStr) {
 strlength = fieldStr.length;
 whspaces = fieldStr.match(/\s/g);
 if(whspaces) {whspaces_count = whspaces.length;} else {whspaces_count = 0;}
 if(whspaces_count == strlength || strlength < 2) {return false;} else {return true;}
}


function spam_check(fieldStr) {
 forbidden_strings = fieldStr.match(/url=|\[\/url\]|http:\/\//i); //  additional Spam-check: 'url=','[/url]','http://' not allowed
 if (forbidden_strings) {return false;} else {return true;}
}