Some Boeing 744's had this facility, but I don't know if any airlines still have this active. On most 744's, there are 3 small blanking plates just above the smaller nosewheel doors where small yellow antennae can be fitted (or were fitted). Optionally, there was an ILS/MLS switch in the cockpit (some aircraft now have an INOP sticker over the "MLS"). The ILS receivers can have MLS modules.
The MLS approach was entered via the FMC CDU (in a similar fashion to the ILS freq/course).
I believe PANC (Anchorage) used to have an MLS approach.
Rgds
NSEU
Last edited by NSEU; 9th Aug 2012 at 00:17.