Zero-day vulnerability in Symantec PGP Whole Disk Encryption

Published at SecurityAffairs and written by Pierluigi Paganini. Based on the explanation, it is buffer overflow case and it claims that it only affecting Windows XP and Windows 2003 (I guess it is Windows 2003 server). There are few questions throw into my mind... 

1. Is the vulnerabilities affecting XP and 2003 32 bits only or also 64 bits OS?

2. Is this relevance since XP and 2003? (Based on NetMarketShares, it seem relevance)

3. What about Windows 7 and Windows 8? Has that been tested although they claimed that it is not affected?

What ever it is, user shall take this seriously especially to those using non-branded and non-tested encryption :)