From Spyware Warrior's site about Stop-sign:
"eAcceleration's Stop-Sign anti-malware scanner was listed on this page primarily because of the company's history of employing deceptive advertising and drive-by-downloads (1, 2, 3, 4). The company was also known for removing and/or disabling competing apps. These objectionable business practices were employed primarily during the years 2002-2003.
Sometime during 2004 the company underwent reorganization. Not only have the worst of the company's download and installation practices been halted, but the company has completely overhauled its stub installer application, giving users much more control over the software modules to be installed on their systems (1, 2).
While testing indicates that the "threat scanner" is still slow and has occasional problems with false positives -- in large part because of the use of heuristics, which cannot be turned off by the user -- we can no longer classify this application as "rogue/suspect." Nonetheless, this anti-malware application -- at least in its current state -- cannot be recommended, given the many excellent competing anti-virus, anti-trojan, and anti-spyware applications that are available (some for free).