Daniel from OSSEC has reported that a couple Antivirus products are currently detecting the Windows version of OSSEC HIDS as malware. They have been notified and will (we hope) be fixing it soon. Currently the products finding it as malware are (in VirusTotal format of Product,  Version, Last Update, Detection Result):

a-squared 4.0.0.73 2009.01.05 Generic.Qhost!IK
BitDefender 7.2 2009.01.05 Generic.Qhost.E185971A
F-Secure 8.0.14470.0 2009.01.05 Suspicious:W32/Malware!Gemini
GData 19 2009.01.05 Generic.Qhost.E185971A
Ikarus T3.1.1.45.0 2009.01.05 Generic.Qhost
Prevx1 V2 2009.01.05 Worm