Is because of a denial of service attack on zonelabs.com (the makers of Zone Alarm). Here is an extract from Blueyonder status page:
"After investigation we have found this problem is affecting other ISP's and not just blueyonder. We have found a possible issue and as a result we have temporarily ceased DNS lookups to click here as well as lockup.zonelabs.com. Customers will be unable to access these sites until further notice.
Access to blueyonder service such as Selfcare, Webmail and Email has greatly improved. However, access may still be slow and intermittent. Further investigation will take place throughout tonight.
Please be advised one again that this issue is affecting other ISP's worldwide and not just blueyonder."