FATAL: Module ppp_compress_18 not found

[powah]

I add this line
alias ppp-compress-18 ppp_mppe
to the /etc/modules.d/ppp file.

# modules-update

# modprobe ppp-compress-18
FATAL: Module ppp_compress_18 not found.

# modprobe ppp_mppe
$ lsmod
Module Size Used by
ppp_mppe 12640 -
via_rhine 19940 -

# cat /proc/version
Linux version 2.6.11-gentoo-r8 (root@rose) (gcc version 3.4.2 (Gentoo Linux 3.4.2-r2, ssp-3.4.1-1, pie-8.7.6.5)) #7 Fri May 13 20:52:58 UTC 2005

How to fix this "Module ppp_compress_18 not found" problem?

[ptrivino]

I add this line
alias ppp-compress-18 ppp_mppe
to the /etc/modules.d/ppp file.

# modules-update

# modprobe ppp-compress-18
FATAL: Module ppp_compress_18 not found.

# modprobe ppp_mppe
$ lsmod
Module Size Used by
ppp_mppe 12640 -
via_rhine 19940 -

# cat /proc/version
Linux version 2.6.11-gentoo-r8 (root@rose) (gcc version 3.4.2 (Gentoo Linux 3.4.2-r2, ssp-3.4.1-1, pie-8.7.6.5)) #7 Fri May 13 20:52:58 UTC 2005

How to fix this "Module ppp_compress_18 not found" problem?

I have little or no clue of the specific problem BUT I noticed the "alias" stmt at the top used dashes "-" while the error message uses underscores "_" - do make sure the syntax/name is correct? FWIW...