Its not updating multiple rows. Its updating multiple columns on a row. Don't know if that makes a difference. I tried the following, but the update across the db is still not occurring. Again, it works fine in my test environment, just not production.
set ANSI_NULLS ON
set QUOTED_IDENTIFIER ON
go
ALTER TRIGGER [trgUpdateExt]
ON [dbo].[tblUser]
FOR UPDATE
AS
DECLARE @ext varchar(5)
DECLARE @user varchar(50)
SELECT @ext = ext, @user = loginname
FROM inserted i
inner join dbo.tblUser tu on tu.loginname = i.loginame
print @ext
print @user
BEGIN
UPDATE test1.dbo.tblUser
Set ext = @ext,
ext2 = @ext
where loginname = @user
UPDATE test1.dbo.tblUser2
Set ext = @ext,
ext2 = @ext
where loginname = @user
END