wrong redirection from j_security_check when user in different role

[dyyyy]

hi i'm using j_security check with weblogic,
with <wls:principal-name>Administrators</wls:principal-name>
to let only administrators access.
the strange thing is that :
if i enter an administrator user/password -> it sends me to the correct page
if i enter a username that does not exist -> it sends me to the error page
if i enter a wrong password -> it sends me to the error page

but if i enter a username/password that exists but that is not an administrator it throws an error (sending me to the default error page of the application), with all relative path images and links broken. and looking at the URL, it is the URL that i should get when entering as an administrator.

in the audit log file, the person's role is being known and i'm getting a failure
this is a part of the log, when logging in a wrong role

#### Audit Record Begin <Nov 25, 2009 10:41:33 AM>  <Severity =SUCCESS>  <<<Event Type = Authentication Audit Event><dany><AUTHENTICATE>>> Audit Record End ####  
#### Audit Record Begin <Nov 25, 2009 10:41:33 AM>  <Severity =INFORMATION>  <<<Event Type = RoleManager Audit Event ><Subject: 2  
    Principal = class weblogic.security.principal.WLSUserImpl("dany")  
    Principal = class weblogic.security.principal.WLSGroupImpl("AppTesters")  
><<url>><type=<url>, application=app, contextPath=/PP, uri=/faces/page/sampleList.jsp, httpMethod=GET><>>> Audit Record End ####  
#### Audit Record Begin <Nov 25, 2009 10:41:33 AM>  <Severity =FAILURE>  <<<Event Type = Authorization Audit Event V2 ><Subject: 2  
    Principal = class weblogic.security.principal.WLSUserImpl("dany")  
    Principal = class weblogic.security.principal.WLSGroupImpl("AppTesters")  
><ONCE><<url>><type=<url>, application=app, contextPath=/PP, uri=/faces/page/sampleList.jsp, httpMethod=GET>>> Audit Record End ####  
#### Audit Record Begin <Nov 25, 2009 10:41:34 AM>  <Severity =FAILURE>  <<<Event Type = Authorization Audit Event V2 ><Subject: 2  
    Principal = class weblogic.security.principal.WLSUserImpl("dany")  
    Principal = class weblogic.security.principal.WLSGroupImpl("AppTesters")  
><ONCE><<url>><type=<url>, application=app, contextPath=/PP, uri=/faces/page/images/error/image.png, httpMethod=GET>>> Audit Record End ####

/faces/page/sampleList.jsp is the page where the user should be redirected if he was an administrator
the error is here
/faces/page/images/error/image.png does not exist, in my code i have a relative path '/images/error/image.png' that shouldn't come from '/faces/page/' (the path for a right login) but from '/common/pages/' (the path where error-page.jsp exists)

thank you for your help (sorry for the long post:p)