ANSI-92 Inner Join Vs. Where Clause Syntax

Having problems rewriting my join condition using the "inner join" syntax.

My query, working with an intersection table:

SELECT Description, EmailAddress
FROM Accounts_Roles r, Accounts_Users u, Accounts_UserRoles ur
WHERE
r.RoleID = ur.RoleID
AND
u.UserID = ur.UserID

This works fine, but i want to write it using 'inner join' style, so I tried:

SELECT Description, EmailAddress
FROM Accounts_Roles r, Accounts_Users u
INNER JOIN Accounts_UserRoles ur
ON
r.RoleID = ur.RoleID
AND
u.UserID = ur.UserID

which gives me an error (The column prefix 'r' does not match with a table name or alias name used in the query.)

Any ideas as to how I'm screwing this up would be appreciated.

Thanks,
Gordon Z