this login is not of the hamachi itself or from hfs, By default, the Simple File Sharing UI is turned on in Windows XP you have to turn it off....
Disable Simple File Sharing
Disabling Simple File Sharing is necessary in order to enable the creation of Access Control Lists for shared disks and folders:
1. Click Start | My Computer | Tools | Folder Options | View.
2. Scroll to the bottom of the list of advanced settings and un-check Use Simple File Sharing (Recommended).
3. Click OK.