Close Connections from Central Server to Local Servers

Hi, We have a Central Server with 10 Local Servers. S.O. RedHat Linux SE 3 Update 4 IDS 7.31.UD1 The problem is some users connect to Central Server using SQL Editor with the same account, then from it connect to local servers. When I monitoring connections on local servers only saw the IP addresses of Central Server. When some data are it's modified and then whant's to know who did it all of them say "I dont know .....". How i can continue with trusted relations between servers, but blocking that account to connect other local servers thru Central Server DataBase Instance. Regards, __________________________________________________ Correo Yahoo! Espacio para todos tus mensajes, antivirus y antispam 'gratis! Reg'strate ya - http://correo.yahoo.com.mx/