http://sisyphus.ru/srpm/BP3/emacs-mode-auctex/get suggests: 

ftp://ftp.altlinux.org/pub/distributions/ALTLinux/backports/3.0/noarch/RPMS.backports/emacs-mode-auctex-11.83-alt0.M30.1.noarch.rpm
ftp://ftp.altlinux.org/pub/distributions/ALTLinux/backports/3.0/noarch/RPMS.backports/emacs-mode-auctex-el-11.83-alt0.M30.1.noarch.rpm
ftp://ftp.altlinux.org/pub/distributions/ALTLinux/backports/3.0/noarch/RPMS.backports/tetex-latex-preview-11.83-alt0.M30.1.noarch.rpm

But those URLs are not OK:

$ wget 'ftp://ftp.altlinux.org/pub/distributions/ALTLinux/backports/3.0/noarch/RPMS.backports/emacs-mode-auctex-11.83-alt0.M30.1.noarch.rpm' 'ftp://ftp.altlinux.org/pub/distributions/ALTLinux/backports/3.0/noarch/RPMS.backports/emacs-mode-auctex-el-11.83-alt0.M30.1.noarch.rpm' 'ftp://ftp.altlinux.org/pub/distributions/ALTLinux/backports/3.0/noarch/RPMS.backports/tetex-latex-preview-11.83-alt0.M30.1.noarch.rpm'
--2008-07-24 18:49:35--  ftp://ftp.altlinux.org/pub/distributions/ALTLinux/backports/3.0/noarch/RPMS.backports/emacs-mode-auctex-11.83-alt0.M30.1.noarch.rpm
           => `emacs-mode-auctex-11.83-alt0.M30.1.noarch.rpm'
Resolving ftp.altlinux.org... 194.107.17.7
Connecting to ftp.altlinux.org|194.107.17.7|:21... connected.
Logging in as anonymous ... Logged in!
==> SYST ... done.    ==> PWD ... done.
==> TYPE I ... done.  ==> CWD /pub/distributions/ALTLinux/backports/3.0/noarch/RPMS.backports ... 
No such directory `pub/distributions/ALTLinux/backports/3.0/noarch/RPMS.backports'.

--2008-07-24 18:49:35--  ftp://ftp.altlinux.org/pub/distributions/ALTLinux/backports/3.0/noarch/RPMS.backports/emacs-mode-auctex-el-11.83-alt0.M30.1.noarch.rpm
           => `emacs-mode-auctex-el-11.83-alt0.M30.1.noarch.rpm'
Connecting to ftp.altlinux.org|194.107.17.7|:21... connected.
Logging in as anonymous ... Logged in!
==> SYST ... done.    ==> PWD ... done.
==> TYPE I ... done.  ==> CWD /pub/distributions/ALTLinux/backports/3.0/noarch/RPMS.backports ... 
No such directory `pub/distributions/ALTLinux/backports/3.0/noarch/RPMS.backports'.

--2008-07-24 18:49:35--  ftp://ftp.altlinux.org/pub/distributions/ALTLinux/backports/3.0/noarch/RPMS.backports/tetex-latex-preview-11.83-alt0.M30.1.noarch.rpm
           => `tetex-latex-preview-11.83-alt0.M30.1.noarch.rpm'
Connecting to ftp.altlinux.org|194.107.17.7|:21... connected.
Logging in as anonymous ... Logged in!
==> SYST ... done.    ==> PWD ... done.
==> TYPE I ... done.  ==> CWD /pub/distributions/ALTLinux/backports/3.0/noarch/RPMS.backports ... 
No such directory `pub/distributions/ALTLinux/backports/3.0/noarch/RPMS.backports'.

$ 

The correct ones are with ".../i586/..." instead of ".../noarch/...":

$ wget 'ftp://ftp.altlinux.org/pub/distributions/ALTLinux/backports/3.0/i586/RPMS.backports/emacs-mode-auctex-11.83-alt0.M30.1.noarch.rpm' 'ftp://ftp.altlinux.org/pub/distributions/ALTLinux/backports/3.0/i586/RPMS.backports/emacs-mode-auctex-el-11.83-alt0.M30.1.noarch.rpm' 'ftp://ftp.altlinux.org/pub/distributions/ALTLinux/backports/3.0/i586/RPMS.backports/tetex-latex-preview-11.83-alt0.M30.1.noarch.rpm'
--2008-07-24 18:50:42--  ftp://ftp.altlinux.org/pub/distributions/ALTLinux/backports/3.0/i586/RPMS.backports/emacs-mode-auctex-11.83-alt0.M30.1.noarch.rpm
           => `emacs-mode-auctex-11.83-alt0.M30.1.noarch.rpm'
Resolving ftp.altlinux.org... 194.107.17.7
Connecting to ftp.altlinux.org|194.107.17.7|:21... connected.
Logging in as anonymous ... Logged in!
==> SYST ... done.    ==> PWD ... done.
==> TYPE I ... done.  ==> CWD /pub/distributions/ALTLinux/backports/3.0/i586/RPMS.backports ... done.
==> SIZE emacs-mode-auctex-11.83-alt0.M30.1.noarch.rpm ... 505673
==> PASV ... done.    ==> RETR emacs-mode-auctex-11.83-alt0.M30.1.noarch.rpm ... done.
Length: 505673 (494K)

100%[==============================================================================================================>] 505 673     --.-K/s   in 0,06s   

2008-07-24 18:50:42 (8,65 MB/s) - `emacs-mode-auctex-11.83-alt0.M30.1.noarch.rpm' saved [505673]

--2008-07-24 18:50:42--  ftp://ftp.altlinux.org/pub/distributions/ALTLinux/backports/3.0/i586/RPMS.backports/emacs-mode-auctex-el-11.83-alt0.M30.1.noarch.rpm
           => `emacs-mode-auctex-el-11.83-alt0.M30.1.noarch.rpm'
Connecting to ftp.altlinux.org|194.107.17.7|:21... connected.
Logging in as anonymous ... Logged in!
==> SYST ... done.    ==> PWD ... done.
==> TYPE I ... done.  ==> CWD /pub/distributions/ALTLinux/backports/3.0/i586/RPMS.backports ... done.
==> SIZE emacs-mode-auctex-el-11.83-alt0.M30.1.noarch.rpm ... 337752
==> PASV ... done.    ==> RETR emacs-mode-auctex-el-11.83-alt0.M30.1.noarch.rpm ... done.
Length: 337752 (330K)

100%[==============================================================================================================>] 337 752     --.-K/s   in 0,05s   

2008-07-24 18:50:42 (6,47 MB/s) - `emacs-mode-auctex-el-11.83-alt0.M30.1.noarch.rpm' saved [337752]

--2008-07-24 18:50:42--  ftp://ftp.altlinux.org/pub/distributions/ALTLinux/backports/3.0/i586/RPMS.backports/tetex-latex-preview-11.83-alt0.M30.1.noarch.rpm
           => `tetex-latex-preview-11.83-alt0.M30.1.noarch.rpm'
Connecting to ftp.altlinux.org|194.107.17.7|:21... connected.
Logging in as anonymous ... Logged in!
==> SYST ... done.    ==> PWD ... done.
==> TYPE I ... done.  ==> CWD /pub/distributions/ALTLinux/backports/3.0/i586/RPMS.backports ... done.
==> SIZE tetex-latex-preview-11.83-alt0.M30.1.noarch.rpm ... 48512
==> PASV ... done.    ==> RETR tetex-latex-preview-11.83-alt0.M30.1.noarch.rpm ... done.
Length: 48512 (47K)

100%[==============================================================================================================>] 48 512      --.-K/s   in 0,01s   

2008-07-24 18:50:42 (4,04 MB/s) - `tetex-latex-preview-11.83-alt0.M30.1.noarch.rpm' saved [48512]

FINISHED --2008-07-24 18:50:42--
Downloaded: 3 files, 871K in 0,1s (7,27 MB/s)
$