Citrix! Windows 2003 using Citrixs

Hello everyone, does anyone run Windows 2000 Adavance Server that uses Citrixs XP Metaframe? Well we have a problem are utilizations goes sky highs on all 3 servers we have. It reachs up to 100%-90, but it does varies. Sometime we have to restart the server because it freezes at 100%. Does anyone else have the same problem? Also i heard Windows 2003 Server fixs the problem, does anyone know if it is true?