Stonesoft StoneGate IPS before 4.0 does not properly decode Fullwidth/Halfwidth Unicode encoded data, which makes it easier for remote attackers to scan or penetrate systems and avoid detection.
http://www.vupen.com/english/advisories/2007/2757
http://www.kb.cert.org/vuls/id/MIMG-72BRKJ
http://www.kb.cert.org/vuls/id/739224