function checkEmailAddress(field,empty_err){var err=false;if(!field){return true;}
if(field.value.length==0){if(empty_err!='Y'){return true;}else{err=true;}}
if(!err&&field.value.replace(/^\s+/g,'').replace(/\s+$/g,'').search(email_validation_regexp)==-1){err=true;}
if(err){alert(txt_email_invalid);field.focus();field.select();}
return!err;}